656420 has 24 divisors (see below), whose sum is σ = 1439424. Its totient is φ = 250976.

The previous prime is 656407. The next prime is 656423. The reversal of 656420 is 24656.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is not an unprimeable number, because it can be changed into a prime (656423) by changing a digit.

656420 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 254 + ... + 1173.

It is an arithmetic number, because the mean of its divisors is an integer number (59976).

2⁶⁵⁶⁴²⁰ is an apocalyptic number.

It is an amenable number.

656420 is an abundant number, since it is smaller than the sum of its proper divisors (783004).

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

656420 is a wasteful number, since it uses less digits than its factorization.

656420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1459 (or 1457 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 656420 is about 810.1975067846. The cubic root of 656420 is about 86.9081692779.

The spelling of 656420 in words is "six hundred fifty-six thousand, four hundred twenty".