256394905290 has 48 divisors (see below), whose sum is σ = 666652279176. Its totient is φ = 68369356800.

The previous prime is 256394905223. The next prime is 256394905313. The reversal of 256394905290 is 92509493652.

It is a happy number.

256394905290 is a `hidden beast` number, since 2 + 5 + 63 + 9 + 490 + 5 + 2 + 90 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 254351774889 + 2043130401 = 504333^2 + 45201^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3866010 + ... + 3931770.

Almost surely, 2^256394905290 is an apocalyptic number.

256394905290 is an abundant number, since it is smaller than the sum of its proper divisors (410257373886).

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

256394905290 is a wasteful number, since it uses less digits than its factorization.

256394905290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 109095 (or 109092 counting only the distinct ones).

The product of its (nonzero) digits is 5248800, while the sum is 54.

The spelling of 256394905290 in words is "two hundred fifty-six billion, three hundred ninety-four million, nine hundred five thousand, two hundred ninety".