390405625 has 10 divisors (see below), whose sum is σ = 487851650. Its totient is φ = 312324000.

The previous prime is 390405607. The next prime is 390405637. The reversal of 390405625 is 526504093.

390405625 = 13971² + 13972².

It can be written as a sum of positive squares in 5 ways, for example, as 195188841 + 195216784 = 13971^2 + 13972^2 .

It is not a de Polignac number, because 390405625 - 2⁷ = 390405497 is a prime.

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 9 ways as a sum of consecutive naturals, for example, 311700 + ... + 312949.

It is an arithmetic number, because the mean of its divisors is an integer number (48785165).

Almost surely, 2^390405625 is an apocalyptic number.

390405625 is the 13972-nd centered square number.

It is an amenable number.

390405625 is a deficient number, since it is larger than the sum of its proper divisors (97446025).

390405625 is an frugal number, since it uses more digits than its factorization.

390405625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 624669 (or 624654 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 34.

The square root of 390405625 is about 19758.6847993484. The cubic root of 390405625 is about 730.8675648979.

The spelling of 390405625 in words is "three hundred ninety million, four hundred five thousand, six hundred twenty-five".