256210638 has 48 divisors (see below), whose sum is σ = 548768640. Its totient is φ = 79726464.

The previous prime is 256210637. The next prime is 256210657. The reversal of 256210638 is 836012652.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 256210599 and 256210608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256210631) 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, 240495 + ... + 241557.

It is an arithmetic number, because the mean of its divisors is an integer number (11432680).

Almost surely, 2^256210638 is an apocalyptic number.

256210638 is an abundant number, since it is smaller than the sum of its proper divisors (292558002).

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

256210638 is a wasteful number, since it uses less digits than its factorization.

256210638 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1241 (or 1224 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 33.

The square root of 256210638 is about 16006.5810840417. The cubic root of 256210638 is about 635.1345225156.

The spelling of 256210638 in words is "two hundred fifty-six million, two hundred ten thousand, six hundred thirty-eight".