16625312681 has 2 divisors, whose sum is σ = 16625312682. Its totient is φ = 16625312680.

The previous prime is 16625312597. The next prime is 16625312689. The reversal of 16625312681 is 18621352661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 8596256656 + 8029056025 = 92716^2 + 89605^2 .

It is a cyclic number.

It is not a de Polignac number, because 16625312681 - 2¹⁸ = 16625050537 is a prime.

It is a super-2 number, since 2×16625312681² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (16625312689) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8312656340 + 8312656341.

It is an arithmetic number, because the mean of its divisors is an integer number (8312656341).

Almost surely, 2^16625312681 is an apocalyptic number.

It is an amenable number.

16625312681 is a deficient number, since it is larger than the sum of its proper divisors (1).

16625312681 is an equidigital number, since it uses as much as digits as its factorization.

16625312681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 103680, while the sum is 41.

The spelling of 16625312681 in words is "sixteen billion, six hundred twenty-five million, three hundred twelve thousand, six hundred eighty-one".