656406400 has 192 divisors, whose sum is σ = 1806134400. Its totient is φ = 234086400.

The previous prime is 656406391. The next prime is 656406403. The reversal of 656406400 is 4604656.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (656406403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1289346 + ... + 1289854.

It is an arithmetic number, because the mean of its divisors is an integer number (9406950).

Almost surely, 2^656406400 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 656406400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (903067200).

656406400 is an abundant number, since it is smaller than the sum of its proper divisors (1149728000).

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

656406400 is a wasteful number, since it uses less digits than its factorization.

656406400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 577 (or 560 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 656406400 is about 25620.4293484711. The cubic root of 656406400 is about 869.0756907308.

The spelling of 656406400 in words is "six hundred fifty-six million, four hundred six thousand, four hundred".