397325781 has 12 divisors (see below), whose sum is σ = 593705580. Its totient is φ = 255749760.

The previous prime is 397325743. The next prime is 397325807. The reversal of 397325781 is 187523793.

It is a happy number.

397325781 is a `hidden beast` number, since 3 + 9 + 73 + 2 + 578 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 165251025 + 232074756 = 12855^2 + 15234^2 .

It is not a de Polignac number, because 397325781 - 2⁷ = 397325653 is a prime.

It is a super-2 number, since 2×397325781² = 315735552494519922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (397325381) 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 11 ways as a sum of consecutive naturals, for example, 760900 + ... + 761421.

It is an arithmetic number, because the mean of its divisors is an integer number (49475465).

Almost surely, 2^397325781 is an apocalyptic number.

It is an amenable number.

397325781 is a deficient number, since it is larger than the sum of its proper divisors (196379799).

397325781 is a wasteful number, since it uses less digits than its factorization.

397325781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1522356 (or 1522353 counting only the distinct ones).

The product of its digits is 317520, while the sum is 45.

The square root of 397325781 is about 19933.0324085424. The cubic root of 397325781 is about 735.1606423828.

The spelling of 397325781 in words is "three hundred ninety-seven million, three hundred twenty-five thousand, seven hundred eighty-one".