256621006 has 8 divisors (see below), whose sum is σ = 387293544. Its totient is φ = 127523160.

The previous prime is 256620983. The next prime is 256621073. The reversal of 256621006 is 600126652.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 393265 + ... + 393916.

It is an arithmetic number, because the mean of its divisors is an integer number (48411693).

Almost surely, 2^256621006 is an apocalyptic number.

256621006 is a deficient number, since it is larger than the sum of its proper divisors (130672538).

256621006 is a wasteful number, since it uses less digits than its factorization.

256621006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 787346.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 256621006 is about 16019.3946826963. The cubic root of 256621006 is about 635.4734361740.

Adding to 256621006 its reverse (600126652), we get a palindrome (856747658).

The spelling of 256621006 in words is "two hundred fifty-six million, six hundred twenty-one thousand, six".