657381820 has 24 divisors (see below), whose sum is σ = 1383357024. Its totient is φ = 262408896.

The previous prime is 657381799. The next prime is 657381821. The reversal of 657381820 is 28183756.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (657381821) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24007 + ... + 43486.

It is an arithmetic number, because the mean of its divisors is an integer number (57639876).

Almost surely, 2^657381820 is an apocalyptic number.

It is an amenable number.

657381820 is an abundant number, since it is smaller than the sum of its proper divisors (725975204).

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

657381820 is a wasteful number, since it uses less digits than its factorization.

657381820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67989 (or 67987 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 40.

The square root of 657381820 is about 25639.4582626077. The cubic root of 657381820 is about 869.5059598728.

The spelling of 657381820 in words is "six hundred fifty-seven million, three hundred eighty-one thousand, eight hundred twenty".