81102537790 has 32 divisors (see below), whose sum is σ = 149495233536. Its totient is φ = 31662036000.

The previous prime is 81102537781. The next prime is 81102537809. The reversal of 81102537790 is 9773520118.

It is a Smith number, since the sum of its digits (43) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (43).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 487915 + ... + 632665.

It is an arithmetic number, because the mean of its divisors is an integer number (4671726048).

Almost surely, 2^81102537790 is an apocalyptic number.

81102537790 is a deficient number, since it is larger than the sum of its proper divisors (68392695746).

81102537790 is a wasteful number, since it uses less digits than its factorization.

81102537790 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 146104.

The product of its (nonzero) digits is 105840, while the sum is 43.

The spelling of 81102537790 in words is "eighty-one billion, one hundred two million, five hundred thirty-seven thousand, seven hundred ninety".