397115778 has 16 divisors (see below), whose sum is σ = 804286080. Its totient is φ = 130696176.

The previous prime is 397115777. The next prime is 397115819. The reversal of 397115778 is 877511793.

It is a super-2 number, since 2×397115778² = 315401882273090568, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (397115773) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 418425 + ... + 419372.

It is an arithmetic number, because the mean of its divisors is an integer number (50267880).

Almost surely, 2^397115778 is an apocalyptic number.

397115778 is an abundant number, since it is smaller than the sum of its proper divisors (407170302).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

397115778 is a wasteful number, since it uses less digits than its factorization.

397115778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 837881.

The product of its digits is 370440, while the sum is 48.

The square root of 397115778 is about 19927.7639990040. The cubic root of 397115778 is about 735.0310986888.

The spelling of 397115778 in words is "three hundred ninety-seven million, one hundred fifteen thousand, seven hundred seventy-eight".