81037652991 has 16 divisors (see below), whose sum is σ = 112854206976. Its totient is φ = 51627524256.

The previous prime is 81037652987. The next prime is 81037653017. The reversal of 81037652991 is 19925673018.

It is not a de Polignac number, because 81037652991 - 2² = 81037652987 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81037652791) 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, 479080 + ... + 625773.

It is an arithmetic number, because the mean of its divisors is an integer number (7053387936).

Almost surely, 2^81037652991 is an apocalyptic number.

81037652991 is a deficient number, since it is larger than the sum of its proper divisors (31816553985).

81037652991 is a wasteful number, since it uses less digits than its factorization.

81037652991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1105942.

The product of its (nonzero) digits is 816480, while the sum is 51.

The spelling of 81037652991 in words is "eighty-one billion, thirty-seven million, six hundred fifty-two thousand, nine hundred ninety-one".