81900038776 has 16 divisors (see below), whose sum is σ = 153665726400. Its totient is φ = 40922511744.

The previous prime is 81900038767. The next prime is 81900038789. The reversal of 81900038776 is 67783000918.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3425800 + ... + 3449623.

It is an arithmetic number, because the mean of its divisors is an integer number (9604107900).

Almost surely, 2^81900038776 is an apocalyptic number.

It is an amenable number.

81900038776 is a deficient number, since it is larger than the sum of its proper divisors (71765687624).

81900038776 is a wasteful number, since it uses less digits than its factorization.

81900038776 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6876918 (or 6876914 counting only the distinct ones).

The product of its (nonzero) digits is 508032, while the sum is 49.

The spelling of 81900038776 in words is "eighty-one billion, nine hundred million, thirty-eight thousand, seven hundred seventy-six".