10156991681 has 2 divisors, whose sum is σ = 10156991682. Its totient is φ = 10156991680.

The previous prime is 10156991609. The next prime is 10156991699. The reversal of 10156991681 is 18619965101.

10156991681 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8516336656 + 1640655025 = 92284^2 + 40505^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-10156991681 is a prime.

It is a super-2 number, since 2×10156991681² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (10156991381) 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 as a sum of consecutive naturals, namely, 5078495840 + 5078495841.

It is an arithmetic number, because the mean of its divisors is an integer number (5078495841).

Almost surely, 2^10156991681 is an apocalyptic number.

It is an amenable number.

10156991681 is a deficient number, since it is larger than the sum of its proper divisors (1).

10156991681 is an equidigital number, since it uses as much as digits as its factorization.

10156991681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 116640, while the sum is 47.

The spelling of 10156991681 in words is "ten billion, one hundred fifty-six million, nine hundred ninety-one thousand, six hundred eighty-one".