256220311 has 8 divisors (see below), whose sum is σ = 271553904. Its totient is φ = 240915840.

The previous prime is 256220309. The next prime is 256220317. The reversal of 256220311 is 113022652.

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

It is not a de Polignac number, because 256220311 - 2¹ = 256220309 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256220317) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12381 + ... + 25801.

It is an arithmetic number, because the mean of its divisors is an integer number (33944238).

Almost surely, 2^256220311 is an apocalyptic number.

256220311 is a deficient number, since it is larger than the sum of its proper divisors (15333593).

256220311 is a wasteful number, since it uses less digits than its factorization.

256220311 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14561.

The product of its (nonzero) digits is 720, while the sum is 22.

The square root of 256220311 is about 16006.8832381573. The cubic root of 256220311 is about 635.1425153908.

Adding to 256220311 its reverse (113022652), we get a palindrome (369242963).

The spelling of 256220311 in words is "two hundred fifty-six million, two hundred twenty thousand, three hundred eleven".