656381 has 4 divisors (see below), whose sum is σ = 716064. Its totient is φ = 596700.

The previous prime is 656377. The next prime is 656389. The reversal of 656381 is 183656.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 656381 - 2² = 656377 is a prime.

It is a super-2 number, since 2×656381² = 861672034322, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (656389) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29825 + ... + 29846.

It is an arithmetic number, because the mean of its divisors is an integer number (179016).

2⁶⁵⁶³⁸¹ is an apocalyptic number.

It is an amenable number.

656381 is a deficient number, since it is larger than the sum of its proper divisors (59683).

656381 is a wasteful number, since it uses less digits than its factorization.

656381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59682.

The product of its digits is 4320, while the sum is 29.

The square root of 656381 is about 810.1734382217. The cubic root of 656381 is about 86.9064480802.

It can be divided in two parts, 65 and 6381, that added together give a palindrome (6446).

The spelling of 656381 in words is "six hundred fifty-six thousand, three hundred eighty-one".