81508352037 has 16 divisors (see below), whose sum is σ = 124262954112. Its totient is φ = 46553794560.

The previous prime is 81508352017. The next prime is 81508352059. The reversal of 81508352037 is 73025380518.

It is not a de Polignac number, because 81508352037 - 2⁷ = 81508351909 is a prime.

It is a super-2 number, since 2×81508352037² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 81508352037.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81508352017) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 888868 + ... + 976269.

It is an arithmetic number, because the mean of its divisors is an integer number (7766434632).

Almost surely, 2^81508352037 is an apocalyptic number.

It is an amenable number.

81508352037 is a deficient number, since it is larger than the sum of its proper divisors (42754602075).

81508352037 is a wasteful number, since it uses less digits than its factorization.

81508352037 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1867228.

The product of its (nonzero) digits is 201600, while the sum is 42.

The spelling of 81508352037 in words is "eighty-one billion, five hundred eight million, three hundred fifty-two thousand, thirty-seven".