1991058902 has 16 divisors (see below), whose sum is σ = 3420096000. Its totient is φ = 851597928.

The previous prime is 1991058877. The next prime is 1991058943. The reversal of 1991058902 is 2098501991.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 135518 + ... + 149489.

It is an arithmetic number, because the mean of its divisors is an integer number (213756000).

Almost surely, 2^1991058902 is an apocalyptic number.

1991058902 is a deficient number, since it is larger than the sum of its proper divisors (1429037098).

1991058902 is a wasteful number, since it uses less digits than its factorization.

1991058902 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 285515.

The product of its (nonzero) digits is 58320, while the sum is 44.

The square root of 1991058902 is about 44621.2830608892. The cubic root of 1991058902 is about 1258.0407321575.

The spelling of 1991058902 in words is "one billion, nine hundred ninety-one million, fifty-eight thousand, nine hundred two".