256405507611 has 16 divisors (see below), whose sum is σ = 373135226880. Its totient is φ = 155321543520.

The previous prime is 256405507591. The next prime is 256405507619. The reversal of 256405507611 is 116705504652.

It is not a de Polignac number, because 256405507611 - 2¹³ = 256405499419 is a prime.

It is not an unprimeable number, because it can be changed into a prime (256405507619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1824571 + ... + 1960068.

It is an arithmetic number, because the mean of its divisors is an integer number (23320951680).

Almost surely, 2^256405507611 is an apocalyptic number.

256405507611 is a deficient number, since it is larger than the sum of its proper divisors (116729719269).

256405507611 is a wasteful number, since it uses less digits than its factorization.

256405507611 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3786706.

The product of its (nonzero) digits is 252000, while the sum is 42.

The spelling of 256405507611 in words is "two hundred fifty-six billion, four hundred five million, five hundred seven thousand, six hundred eleven".