213404256 has 72 divisors (see below), whose sum is σ = 653562000. Its totient is φ = 65661696.

The previous prime is 213404237. The next prime is 213404263. The reversal of 213404256 is 652404312.

213404256 is a `hidden beast` number, since 2 + 1 + 3 + 404 + 256 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 24756 + ... + 32243.

It is an arithmetic number, because the mean of its divisors is an integer number (9077250).

Almost surely, 2^213404256 is an apocalyptic number.

213404256 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

213404256 is an abundant number, since it is smaller than the sum of its proper divisors (440157744).

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

213404256 is a wasteful number, since it uses less digits than its factorization.

213404256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57028 (or 57017 counting only the distinct ones).

The product of its (nonzero) digits is 5760, while the sum is 27.

The square root of 213404256 is about 14608.3625365747. The cubic root of 213404256 is about 597.5868407827.

Adding to 213404256 its reverse (652404312), we get a palindrome (865808568).

The spelling of 213404256 in words is "two hundred thirteen million, four hundred four thousand, two hundred fifty-six".