657996240 has 160 divisors (see below), whose sum is σ = 2272997376. Its totient is φ = 156090880.

The previous prime is 657996233. The next prime is 657996247. The reversal of 657996240 is 42699756.

It is an interprime number because it is at equal distance from previous prime (657996233) and next prime (657996247).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 657996240.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (657996247) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 121429 + ... + 126731.

Almost surely, 2^657996240 is an apocalyptic number.

657996240 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 657996240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1136498688).

657996240 is an abundant number, since it is smaller than the sum of its proper divisors (1615001136).

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

657996240 is a wasteful number, since it uses less digits than its factorization.

657996240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5377 (or 5371 counting only the distinct ones).

The product of its (nonzero) digits is 816480, while the sum is 48.

The square root of 657996240 is about 25651.4373866261. The cubic root of 657996240 is about 869.7767692560.

The spelling of 657996240 in words is "six hundred fifty-seven million, nine hundred ninety-six thousand, two hundred forty".