81229275057 has 32 divisors (see below), whose sum is σ = 131318579200. Its totient is φ = 43627465728.

The previous prime is 81229275031. The next prime is 81229275073. The reversal of 81229275057 is 75057292218.

It is not a de Polignac number, because 81229275057 - 2¹² = 81229270961 is a prime.

It is the 285008-th Hogben number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 81229274997 and 81229275015.

It is not an unprimeable number, because it can be changed into a prime (81229274057) by changing a digit.

It is a nontrivial repunit in base 285007.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 750832 + ... + 852177.

It is an arithmetic number, because the mean of its divisors is an integer number (4103705600).

Almost surely, 2^81229275057 is an apocalyptic number.

It is an amenable number.

81229275057 is a deficient number, since it is larger than the sum of its proper divisors (50089304143).

81229275057 is a wasteful number, since it uses less digits than its factorization.

81229275057 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1603165.

The product of its (nonzero) digits is 705600, while the sum is 48.

The spelling of 81229275057 in words is "eighty-one billion, two hundred twenty-nine million, two hundred seventy-five thousand, fifty-seven".