398457765 has 16 divisors (see below), whose sum is σ = 708369600. Its totient is φ = 212510736.

The previous prime is 398457733. The next prime is 398457769. The reversal of 398457765 is 567754893.

398457765 is a `hidden beast` number, since 3 + 9 + 8 + 4 + 577 + 65 = 666.

It is not a de Polignac number, because 398457765 - 2⁵ = 398457733 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (398457769) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1475635 + ... + 1475904.

It is an arithmetic number, because the mean of its divisors is an integer number (44273100).

Almost surely, 2^398457765 is an apocalyptic number.

It is an amenable number.

398457765 is a deficient number, since it is larger than the sum of its proper divisors (309911835).

398457765 is a wasteful number, since it uses less digits than its factorization.

398457765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2951553 (or 2951547 counting only the distinct ones).

The product of its digits is 6350400, while the sum is 54.

The square root of 398457765 is about 19961.4068892952. The cubic root of 398457765 is about 735.8581397243.

The spelling of 398457765 in words is "three hundred ninety-eight million, four hundred fifty-seven thousand, seven hundred sixty-five".