397749631 has 2 divisors, whose sum is σ = 397749632. Its totient is φ = 397749630.

The previous prime is 397749607. The next prime is 397749659. The reversal of 397749631 is 136947793.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 397749631 - 2¹⁵ = 397716863 is a prime.

It is a super-2 number, since 2×397749631² = 316409537921272322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (397749601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 198874815 + 198874816.

It is an arithmetic number, because the mean of its divisors is an integer number (198874816).

Almost surely, 2^397749631 is an apocalyptic number.

397749631 is a deficient number, since it is larger than the sum of its proper divisors (1).

397749631 is an equidigital number, since it uses as much as digits as its factorization.

397749631 is an evil number, because the sum of its binary digits is even.

The product of its digits is 857304, while the sum is 49.

The square root of 397749631 is about 19943.6614241217. The cubic root of 397749631 is about 735.4219620345.

The spelling of 397749631 in words is "three hundred ninety-seven million, seven hundred forty-nine thousand, six hundred thirty-one".