397974757 has 4 divisors (see below), whose sum is σ = 403426540. Its totient is φ = 392522976.

The previous prime is 397974697. The next prime is 397974763. The reversal of 397974757 is 757479793.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 318301281 + 79673476 = 17841^2 + 8926^2 .

It is a cyclic number.

It is not a de Polignac number, because 397974757 - 2¹¹ = 397972709 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (397974457) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2725782 + ... + 2725927.

It is an arithmetic number, because the mean of its divisors is an integer number (100856635).

Almost surely, 2^397974757 is an apocalyptic number.

It is an amenable number.

397974757 is a deficient number, since it is larger than the sum of its proper divisors (5451783).

397974757 is an equidigital number, since it uses as much as digits as its factorization.

397974757 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5451782.

The product of its digits is 11668860, while the sum is 58.

The square root of 397974757 is about 19949.3046745996. The cubic root of 397974757 is about 735.5606852961.

The spelling of 397974757 in words is "three hundred ninety-seven million, nine hundred seventy-four thousand, seven hundred fifty-seven".