256890066 has 32 divisors (see below), whose sum is σ = 526065408. Its totient is φ = 83606400.

The previous prime is 256890061. The next prime is 256890107. The reversal of 256890066 is 660098652.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (256890061) 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 15 ways as a sum of consecutive naturals, for example, 41335 + ... + 47141.

It is an arithmetic number, because the mean of its divisors is an integer number (16439544).

Almost surely, 2^256890066 is an apocalyptic number.

256890066 is an abundant number, since it is smaller than the sum of its proper divisors (269175342).

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

256890066 is a wasteful number, since it uses less digits than its factorization.

256890066 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5986.

The product of its (nonzero) digits is 155520, while the sum is 42.

The square root of 256890066 is about 16027.7904278787. The cubic root of 256890066 is about 635.6954506849.

The spelling of 256890066 in words is "two hundred fifty-six million, eight hundred ninety thousand, sixty-six".