397780957 has 4 divisors (see below), whose sum is σ = 454606816. Its totient is φ = 340955100.

The previous prime is 397780937. The next prime is 397780987. The reversal of 397780957 is 759087793.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 397780957 - 2⁷ = 397780829 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 397780898 and 397780907.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (397780927) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 28412919 + ... + 28412932.

It is an arithmetic number, because the mean of its divisors is an integer number (113651704).

Almost surely, 2^397780957 is an apocalyptic number.

It is an amenable number.

397780957 is a deficient number, since it is larger than the sum of its proper divisors (56825859).

397780957 is an equidigital number, since it uses as much as digits as its factorization.

397780957 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 56825858.

The product of its (nonzero) digits is 3333960, while the sum is 55.

The square root of 397780957 is about 19944.4467709686. The cubic root of 397780957 is about 735.4412683366.

The spelling of 397780957 in words is "three hundred ninety-seven million, seven hundred eighty thousand, nine hundred fifty-seven".