390392505 has 48 divisors (see below), whose sum is σ = 724009104. Its totient is φ = 193904640.

The previous prime is 390392503. The next prime is 390392521. The reversal of 390392505 is 505293093.

It can be written as a sum of positive squares in 8 ways, for example, as 12362256 + 378030249 = 3516^2 + 19443^2 .

It is not a de Polignac number, because 390392505 - 2¹ = 390392503 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 390392505.

It is not an unprimeable number, because it can be changed into a prime (390392503) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 71575 + ... + 76835.

It is an arithmetic number, because the mean of its divisors is an integer number (15083523).

Almost surely, 2^390392505 is an apocalyptic number.

It is an amenable number.

390392505 is a deficient number, since it is larger than the sum of its proper divisors (333616599).

390392505 is a wasteful number, since it uses less digits than its factorization.

390392505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5386 (or 5383 counting only the distinct ones).

The product of its (nonzero) digits is 36450, while the sum is 36.

The square root of 390392505 is about 19758.3527906554. The cubic root of 390392505 is about 730.8593776099.

The spelling of 390392505 in words is "three hundred ninety million, three hundred ninety-two thousand, five hundred five".