391497225 has 24 divisors (see below), whose sum is σ = 739744320. Its totient is φ = 178969920.

The previous prime is 391497221. The next prime is 391497229. The reversal of 391497225 is 522794193.

It is an interprime number because it is at equal distance from previous prime (391497221) and next prime (391497229).

It is not a de Polignac number, because 391497225 - 2² = 391497221 is a prime.

It is not an unprimeable number, because it can be changed into a prime (391497221) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 372330 + ... + 373379.

It is an arithmetic number, because the mean of its divisors is an integer number (30822680).

Almost surely, 2^391497225 is an apocalyptic number.

391497225 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

It is an amenable number.

391497225 is a deficient number, since it is larger than the sum of its proper divisors (348247095).

391497225 is a wasteful number, since it uses less digits than its factorization.

391497225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 745729 (or 745724 counting only the distinct ones).

The product of its digits is 136080, while the sum is 42.

The square root of 391497225 is about 19786.2888132161. The cubic root of 391497225 is about 731.5481157186.

The spelling of 391497225 in words is "three hundred ninety-one million, four hundred ninety-seven thousand, two hundred twenty-five".