256321670 has 16 divisors (see below), whose sum is σ = 503322768. Its totient is φ = 93207840.

The previous prime is 256321651. The next prime is 256321717. The reversal of 256321670 is 76123652.

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1164989 + ... + 1165208.

It is an arithmetic number, because the mean of its divisors is an integer number (31457673).

Almost surely, 2^256321670 is an apocalyptic number.

256321670 is a deficient number, since it is larger than the sum of its proper divisors (247001098).

256321670 is a wasteful number, since it uses less digits than its factorization.

256321670 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2330215.

The product of its (nonzero) digits is 15120, while the sum is 32.

The square root of 256321670 is about 16010.0490317800. The cubic root of 256321670 is about 635.2262570254.

The spelling of 256321670 in words is "two hundred fifty-six million, three hundred twenty-one thousand, six hundred seventy".