391000020 has 24 divisors (see below), whose sum is σ = 1094800224. Its totient is φ = 104266656.

The previous prime is 390999997. The next prime is 391000033. The reversal of 391000020 is 20000193.

It is a Harshad number since it is a multiple of its sum of digits (15).

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 7 ways as a sum of consecutive naturals, for example, 3258274 + ... + 3258393.

It is an arithmetic number, because the mean of its divisors is an integer number (45616676).

Almost surely, 2^391000020 is an apocalyptic number.

391000020 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

391000020 is an abundant number, since it is smaller than the sum of its proper divisors (703800204).

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

391000020 is a wasteful number, since it uses less digits than its factorization.

391000020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6516679 (or 6516677 counting only the distinct ones).

The product of its (nonzero) digits is 54, while the sum is 15.

The square root of 391000020 is about 19773.7204390069. The cubic root of 391000020 is about 731.2382936251.

The spelling of 391000020 in words is "three hundred ninety-one million, twenty", and thus it is an aban number.