81757255157526 has 64 divisors (see below), whose sum is σ = 185262827633856. Its totient is φ = 23879204352000.

The previous prime is 81757255157449. The next prime is 81757255157527. The reversal of 81757255157526 is 62575155275718.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81757255157527) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 345356275 + ... + 345592926.

It is an arithmetic number, because the mean of its divisors is an integer number (2894731681779).

Almost surely, 2^{81757255157526} is an apocalyptic number.

81757255157526 is an abundant number, since it is smaller than the sum of its proper divisors (103505572476330).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81757255157526 is a wasteful number, since it uses less digits than its factorization.

81757255157526 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 690949297.

The product of its digits is 205800000, while the sum is 66.

The spelling of 81757255157526 in words is "eighty-one trillion, seven hundred fifty-seven billion, two hundred fifty-five million, one hundred fifty-seven thousand, five hundred twenty-six".