391212972 has 36 divisors (see below), whose sum is σ = 998151336. Its totient is φ = 129184320.

The previous prime is 391212967. The next prime is 391213001. The reversal of 391212972 is 279212193.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×391212972² = 306095178922145568, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

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 11 ways as a sum of consecutive naturals, for example, 46929 + ... + 54632.

It is an arithmetic number, because the mean of its divisors is an integer number (27726426).

Almost surely, 2^391212972 is an apocalyptic number.

It is an amenable number.

391212972 is an abundant number, since it is smaller than the sum of its proper divisors (606938364).

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

391212972 is a wasteful number, since it uses less digits than its factorization.

391212972 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101678 (or 101673 counting only the distinct ones).

The product of its digits is 13608, while the sum is 36.

The square root of 391212972 is about 19779.1044286641. The cubic root of 391212972 is about 731.3710220035.

The spelling of 391212972 in words is "three hundred ninety-one million, two hundred twelve thousand, nine hundred seventy-two".