397440997 has 2 divisors, whose sum is σ = 397440998. Its totient is φ = 397440996.

The previous prime is 397440983. The next prime is 397441073. The reversal of 397440997 is 799044793.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 392396481 + 5044516 = 19809^2 + 2246^2 .

It is an emirp because it is prime and its reverse (799044793) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-397440997 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (397440497) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 198720498 + 198720499.

It is an arithmetic number, because the mean of its divisors is an integer number (198720499).

Almost surely, 2^397440997 is an apocalyptic number.

It is an amenable number.

397440997 is a deficient number, since it is larger than the sum of its proper divisors (1).

397440997 is an equidigital number, since it uses as much as digits as its factorization.

397440997 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1714608, while the sum is 52.

The square root of 397440997 is about 19935.9222761326. The cubic root of 397440997 is about 735.2316958160.

The spelling of 397440997 in words is "three hundred ninety-seven million, four hundred forty thousand, nine hundred ninety-seven".