397643131 has 4 divisors (see below), whose sum is σ = 397912032. Its totient is φ = 397374232.

The previous prime is 397643117. The next prime is 397643143. The reversal of 397643131 is 131346793.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 131346793 = 113 ⋅1162361.

It is a cyclic number.

It is not a de Polignac number, because 397643131 - 2⁷ = 397643003 is a prime.

It is a super-2 number, since 2×397643131² = 316240119262966322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (397643101) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 132220 + ... + 135193.

It is an arithmetic number, because the mean of its divisors is an integer number (99478008).

Almost surely, 2^397643131 is an apocalyptic number.

397643131 is a deficient number, since it is larger than the sum of its proper divisors (268901).

397643131 is a wasteful number, since it uses less digits than its factorization.

397643131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 268900.

The product of its digits is 40824, while the sum is 37.

The square root of 397643131 is about 19940.9912241092. The cubic root of 397643131 is about 735.3563182020.

The spelling of 397643131 in words is "three hundred ninety-seven million, six hundred forty-three thousand, one hundred thirty-one".