399190194225 has 81 divisors (see below), whose sum is σ = 726181143363. Its totient is φ = 209621053440.

The previous prime is 399190194163. The next prime is 399190194229. The reversal of 399190194225 is 522491091993.

The square root of 399190194225 is 631815.

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

399190194225 is a `hidden beast` number, since 39 + 91 + 90 + 19 + 422 + 5 = 666.

It can be written as a sum of positive squares in 13 ways, for example, as 9799218081 + 389390976144 = 98991^2 + 624012^2 .

It is not a de Polignac number, because 399190194225 - 2²⁵ = 399156639793 is a prime.

It is a super-2 number, since 2×399190194225² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (399190194229) by changing a digit.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 691837137 + ... + 691837713.

Almost surely, 2^399190194225 is an apocalyptic number.

399190194225 is the 631815-th square number.

399190194225 is the 315908-th centered octagonal number.

It is an amenable number.

399190194225 is a deficient number, since it is larger than the sum of its proper divisors (326990949138).

399190194225 is an frugal number, since it uses more digits than its factorization.

399190194225 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1316 (or 658 counting only the distinct ones).

The product of its (nonzero) digits is 1574640, while the sum is 54.

The spelling of 399190194225 in words is "three hundred ninety-nine billion, one hundred ninety million, one hundred ninety-four thousand, two hundred twenty-five".