391900977 has 32 divisors (see below), whose sum is σ = 645442560. Its totient is φ = 233383680.

The previous prime is 391900969. The next prime is 391900991. The reversal of 391900977 is 779009193.

It is not a de Polignac number, because 391900977 - 2³ = 391900969 is a prime.

It is not an unprimeable number, because it can be changed into a prime (391900997) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 7128 + ... + 28889.

It is an arithmetic number, because the mean of its divisors is an integer number (20170080).

Almost surely, 2^391900977 is an apocalyptic number.

It is an amenable number.

391900977 is a deficient number, since it is larger than the sum of its proper divisors (253541583).

391900977 is a wasteful number, since it uses less digits than its factorization.

391900977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36070 (or 36064 counting only the distinct ones).

The product of its (nonzero) digits is 107163, while the sum is 45.

The square root of 391900977 is about 19796.4890068921. The cubic root of 391900977 is about 731.7995117418.

The spelling of 391900977 in words is "three hundred ninety-one million, nine hundred thousand, nine hundred seventy-seven".