256291071 has 4 divisors (see below), whose sum is σ = 341721432. Its totient is φ = 170860712.

The previous prime is 256291033. The next prime is 256291097. The reversal of 256291071 is 170192652.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 256291071 - 2¹³ = 256282879 is a prime.

It is a super-2 number, since 2×256291071² = 131370226148654082, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256291471) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42715176 + ... + 42715181.

It is an arithmetic number, because the mean of its divisors is an integer number (85430358).

Almost surely, 2^256291071 is an apocalyptic number.

256291071 is a deficient number, since it is larger than the sum of its proper divisors (85430361).

256291071 is an equidigital number, since it uses as much as digits as its factorization.

256291071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85430360.

The product of its (nonzero) digits is 7560, while the sum is 33.

The square root of 256291071 is about 16009.0933846986. The cubic root of 256291071 is about 635.2009788118.

The spelling of 256291071 in words is "two hundred fifty-six million, two hundred ninety-one thousand, seventy-one".