81629992790 has 32 divisors (see below), whose sum is σ = 154719180000. Its totient is φ = 30923106048.

The previous prime is 81629992789. The next prime is 81629992819. The reversal of 81629992790 is 9729992618.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 508856 + ... + 649764.

It is an arithmetic number, because the mean of its divisors is an integer number (4834974375).

Almost surely, 2^81629992790 is an apocalyptic number.

81629992790 is a deficient number, since it is larger than the sum of its proper divisors (73089187210).

81629992790 is a wasteful number, since it uses less digits than its factorization.

81629992790 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143984.

The product of its (nonzero) digits is 8817984, while the sum is 62.

The spelling of 81629992790 in words is "eighty-one billion, six hundred twenty-nine million, nine hundred ninety-two thousand, seven hundred ninety".