81164244902 has 16 divisors (see below), whose sum is σ = 132271755840. Its totient is φ = 37128911232.

The previous prime is 81164244877. The next prime is 81164244907. The reversal of 81164244902 is 20944246118.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 81164244902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81164244907) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13809902 + ... + 13815777.

It is an arithmetic number, because the mean of its divisors is an integer number (8266984740).

Almost surely, 2^81164244902 is an apocalyptic number.

81164244902 is a deficient number, since it is larger than the sum of its proper divisors (51107510938).

81164244902 is a wasteful number, since it uses less digits than its factorization.

81164244902 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27625807.

The product of its (nonzero) digits is 110592, while the sum is 41.

The spelling of 81164244902 in words is "eighty-one billion, one hundred sixty-four million, two hundred forty-four thousand, nine hundred two".