397739521 has 16 divisors (see below), whose sum is σ = 429004800. Its totient is φ = 367562448.

The previous prime is 397739513. The next prime is 397739539. The reversal of 397739521 is 125937793.

It is not a de Polignac number, because 397739521 - 2³ = 397739513 is a prime.

It is not an unprimeable number, because it can be changed into a prime (397739921) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 373636 + ... + 374698.

It is an arithmetic number, because the mean of its divisors is an integer number (26812800).

Almost surely, 2^397739521 is an apocalyptic number.

It is an amenable number.

397739521 is a deficient number, since it is larger than the sum of its proper divisors (31265279).

397739521 is a wasteful number, since it uses less digits than its factorization.

397739521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1548.

The product of its digits is 357210, while the sum is 46.

The square root of 397739521 is about 19943.4079585210. The cubic root of 397739521 is about 735.4157309967.

It can be divided in two parts, 39773 and 9521, that added together give a palindrome (49294).

The spelling of 397739521 in words is "three hundred ninety-seven million, seven hundred thirty-nine thousand, five hundred twenty-one".