656773920 has 480 divisors, whose sum is σ = 2687198976. Its totient is φ = 149299200.

The previous prime is 656773891. The next prime is 656773921. The reversal of 656773920 is 29377656.

It is a tau number, because it is divible by the number of its divisors (480).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (656773921) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 2423385 + ... + 2423655.

Almost surely, 2^656773920 is an apocalyptic number.

656773920 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 656773920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1343599488).

656773920 is an abundant number, since it is smaller than the sum of its proper divisors (2030425056).

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

656773920 is a wasteful number, since it uses less digits than its factorization.

656773920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 326 (or 309 counting only the distinct ones).

The product of its (nonzero) digits is 476280, while the sum is 45.

The square root of 656773920 is about 25627.6007460706. The cubic root of 656773920 is about 869.2378581043.

The spelling of 656773920 in words is "six hundred fifty-six million, seven hundred seventy-three thousand, nine hundred twenty".