91943838990 has 64 divisors (see below), whose sum is σ = 253092741120. Its totient is φ = 23727440160.

The previous prime is 91943838941. The next prime is 91943839049. The reversal of 91943838990 is 9983834919.

It is a happy number.

91943838990 is a `hidden beast` number, since 9 + 1 + 94 + 383 + 89 + 90 = 666.

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 31 ways as a sum of consecutive naturals, for example, 5484094 + ... + 5500833.

It is an arithmetic number, because the mean of its divisors is an integer number (3954574080).

Almost surely, 2^91943838990 is an apocalyptic number.

91943838990 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

91943838990 is an abundant number, since it is smaller than the sum of its proper divisors (161148902130).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91943838990 is a wasteful number, since it uses less digits than its factorization.

91943838990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10984974 (or 10984968 counting only the distinct ones).

The product of its (nonzero) digits is 15116544, while the sum is 63.

The spelling of 91943838990 in words is "ninety-one billion, nine hundred forty-three million, eight hundred thirty-eight thousand, nine hundred ninety".