256990625 has 12 divisors (see below), whose sum is σ = 321221628. Its totient is φ = 205590000.

The previous prime is 256990603. The next prime is 256990633. The reversal of 256990625 is 526099652.

It can be written as a sum of positive squares in 6 ways, for example, as 137569441 + 119421184 = 11729^2 + 10928^2 .

It is not a de Polignac number, because 256990625 - 2⁸ = 256990369 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 37994 + ... + 44243.

It is an arithmetic number, because the mean of its divisors is an integer number (26768469).

Almost surely, 2^256990625 is an apocalyptic number.

256990625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

256990625 is a deficient number, since it is larger than the sum of its proper divisors (64231003).

256990625 is an frugal number, since it uses more digits than its factorization.

256990625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82262 (or 82242 counting only the distinct ones).

The product of its (nonzero) digits is 291600, while the sum is 44.

The square root of 256990625 is about 16030.9271409984. The cubic root of 256990625 is about 635.7783870171.

The spelling of 256990625 in words is "two hundred fifty-six million, nine hundred ninety thousand, six hundred twenty-five".