7828637681 has 2 divisors, whose sum is σ = 7828637682. Its totient is φ = 7828637680.

The previous prime is 7828637653. The next prime is 7828637699. The reversal of 7828637681 is 1867368287.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5350191025 + 2478446656 = 73145^2 + 49784^2 .

It is an emirp because it is prime and its reverse (1867368287) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7828637681 is a prime.

It is a super-2 number, since 2×7828637681² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (7828637611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3914318840 + 3914318841.

It is an arithmetic number, because the mean of its divisors is an integer number (3914318841).

Almost surely, 2^7828637681 is an apocalyptic number.

It is an amenable number.

7828637681 is a deficient number, since it is larger than the sum of its proper divisors (1).

7828637681 is an equidigital number, since it uses as much as digits as its factorization.

7828637681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5419008, while the sum is 56.

The square root of 7828637681 is about 88479.5890643712. The cubic root of 7828637681 is about 1985.6166138228.

The spelling of 7828637681 in words is "seven billion, eight hundred twenty-eight million, six hundred thirty-seven thousand, six hundred eighty-one".