657988 has 12 divisors (see below), whose sum is σ = 1157632. Its totient is φ = 327240.

The previous prime is 657983. The next prime is 658001. The reversal of 657988 is 889756.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (657983) 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, 781 + ... + 1387.

2⁶⁵⁷⁹⁸⁸ is an apocalyptic number.

It is an amenable number.

657988 is a deficient number, since it is larger than the sum of its proper divisors (499644).

657988 is a wasteful number, since it uses less digits than its factorization.

657988 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 882 (or 880 counting only the distinct ones).

The product of its digits is 120960, while the sum is 43.

The square root of 657988 is about 811.1645948881. The cubic root of 657988 is about 86.9773138541.

The spelling of 657988 in words is "six hundred fifty-seven thousand, nine hundred eighty-eight".