7636867981 has 8 divisors (see below), whose sum is σ = 7708872600. Its totient is φ = 7564898880.

The previous prime is 7636867943. The next prime is 7636868051. The reversal of 7636867981 is 1897686367.

It can be written as a sum of positive squares in 4 ways, for example, as 1774515625 + 5862352356 = 42125^2 + 76566^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 7636867981 - 2³¹ = 5489384333 is a prime.

It is a super-2 number, since 2×7636867981² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7636867681) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 651351 + ... + 662971.

It is an arithmetic number, because the mean of its divisors is an integer number (963609075).

Almost surely, 2^7636867981 is an apocalyptic number.

It is an amenable number.

7636867981 is a deficient number, since it is larger than the sum of its proper divisors (72004619).

7636867981 is a wasteful number, since it uses less digits than its factorization.

7636867981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17759.

The product of its digits is 18289152, while the sum is 61.

The square root of 7636867981 is about 87389.1754223599. The cubic root of 7636867981 is about 1969.2692266635.

The spelling of 7636867981 in words is "seven billion, six hundred thirty-six million, eight hundred sixty-seven thousand, nine hundred eighty-one".