81752761010631 has 4 divisors (see below), whose sum is σ = 109003681347512. Its totient is φ = 54501840673752.

The previous prime is 81752761010623. The next prime is 81752761010639. The reversal of 81752761010631 is 13601016725718.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (81752761010623) and next prime (81752761010639).

It is not a de Polignac number, because 81752761010631 - 2³ = 81752761010623 is a prime.

It is a super-2 number, since 2×81752761010631² (a number of 29 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 (81752761010639) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13625460168436 + ... + 13625460168441.

It is an arithmetic number, because the mean of its divisors is an integer number (27250920336878).

Almost surely, 2^{81752761010631} is an apocalyptic number.

81752761010631 is a deficient number, since it is larger than the sum of its proper divisors (27250920336881).

81752761010631 is a wasteful number, since it uses less digits than its factorization.

81752761010631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27250920336880.

The product of its (nonzero) digits is 423360, while the sum is 48.

The spelling of 81752761010631 in words is "eighty-one trillion, seven hundred fifty-two billion, seven hundred sixty-one million, ten thousand, six hundred thirty-one".