391982427225 has 45 divisors (see below), whose sum is σ = 726139146733. Its totient is φ = 209042268480.

The previous prime is 391982427223. The next prime is 391982427251. The reversal of 391982427225 is 522724289193.

The square root of 391982427225 is 626085.

It is a perfect power (a square), and thus also a powerful number.

391982427225 is a `hidden beast` number, since 3 + 9 + 198 + 2 + 427 + 2 + 25 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 11269449 + 391971157776 = 3357^2 + 626076^2 .

It is a tau number, because it is divible by the number of its divisors (45).

It is not a de Polignac number, because 391982427225 - 2¹ = 391982427223 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (391982427223) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 28166869 + ... + 28180781.

Almost surely, 2^391982427225 is an apocalyptic number.

391982427225 is the 626085-th square number.

391982427225 is the 313043-rd centered octagonal number.

It is an amenable number.

391982427225 is a deficient number, since it is larger than the sum of its proper divisors (334156719508).

391982427225 is an frugal number, since it uses more digits than its factorization.

391982427225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27848 (or 13921 counting only the distinct ones).

The product of its digits is 4354560, while the sum is 54.

The spelling of 391982427225 in words is "three hundred ninety-one billion, nine hundred eighty-two million, four hundred twenty-seven thousand, two hundred twenty-five".