256667623 has 8 divisors (see below), whose sum is σ = 260741376. Its totient is φ = 252617400.

The previous prime is 256667617. The next prime is 256667633. The reversal of 256667623 is 326766652.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 256667623 - 2⁵ = 256667591 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 256667623.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256667633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16788 + ... + 28198.

It is an arithmetic number, because the mean of its divisors is an integer number (32592672).

Almost surely, 2^256667623 is an apocalyptic number.

256667623 is a deficient number, since it is larger than the sum of its proper divisors (4073753).

256667623 is a wasteful number, since it uses less digits than its factorization.

256667623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11765.

The product of its digits is 544320, while the sum is 43.

The square root of 256667623 is about 16020.8496341486. The cubic root of 256667623 is about 635.5119132418.

The spelling of 256667623 in words is "two hundred fifty-six million, six hundred sixty-seven thousand, six hundred twenty-three".