397665242 has 16 divisors (see below), whose sum is σ = 647077032. Its totient is φ = 182196480.

The previous prime is 397665221. The next prime is 397665253. The reversal of 397665242 is 242566793.

It can be written as a sum of positive squares in 4 ways, for example, as 258212761 + 139452481 = 16069^2 + 11809^2 .

It is a junction number, because it is equal to n+sod(n) for n = 397665193 and 397665202.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 52259 + ... + 59382.

Almost surely, 2^397665242 is an apocalyptic number.

397665242 is a deficient number, since it is larger than the sum of its proper divisors (249411790).

397665242 is a wasteful number, since it uses less digits than its factorization.

397665242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111793.

The product of its digits is 544320, while the sum is 44.

The square root of 397665242 is about 19941.5456271574. The cubic root of 397665242 is about 735.3699478119.

The spelling of 397665242 in words is "three hundred ninety-seven million, six hundred sixty-five thousand, two hundred forty-two".