7663426681 has 3 divisors (see below), whose sum is σ = 7663514223. Its totient is φ = 7663339140.

The previous prime is 7663426663. The next prime is 7663426711. The reversal of 7663426681 is 1866243667.

The square root of 7663426681 is 87541.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 1866243667 = 23 ⋅81141029.

It can be written as a sum of positive squares in only one way, i.e., 3394111081 + 4269315600 = 58259^2 + 65340^2 .

It is not a de Polignac number, because 7663426681 - 2⁷ = 7663426553 is a prime.

It is a super-2 number, since 2×7663426681² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7663426601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 43771 + ... + 131311.

It is an arithmetic number, because the mean of its divisors is an integer number (2554504741).

Almost surely, 2^7663426681 is an apocalyptic number.

7663426681 is the 87541-st square number.

7663426681 is the 43771-st centered octagonal number.

It is an amenable number.

7663426681 is a deficient number, since it is larger than the sum of its proper divisors (87542).

7663426681 is an frugal number, since it uses more digits than its factorization.

7663426681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 175082 (or 87541 counting only the distinct ones).

The product of its digits is 1741824, while the sum is 49.

The cubic root of 7663426681 is about 1971.5494248791.

Multiplying 7663426681 by its sum of digits (49), we get a square (375507907369 = 612787²).

The spelling of 7663426681 in words is "seven billion, six hundred sixty-three million, four hundred twenty-six thousand, six hundred eighty-one".