256742431 has 8 divisors (see below), whose sum is σ = 281939328. Its totient is φ = 231855000.

The previous prime is 256742429. The next prime is 256742443. The reversal of 256742431 is 134247652.

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

It is a cyclic number.

It is not a de Polignac number, because 256742431 - 2¹ = 256742429 is a prime.

It is a super-2 number, since 2×256742431² = 131833351751579522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256742401) 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, 75625 + ... + 78946.

It is an arithmetic number, because the mean of its divisors is an integer number (35242416).

Almost surely, 2^256742431 is an apocalyptic number.

256742431 is a deficient number, since it is larger than the sum of its proper divisors (25196897).

256742431 is a wasteful number, since it uses less digits than its factorization.

256742431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154733.

The product of its digits is 40320, while the sum is 34.

The square root of 256742431 is about 16023.1841716932. The cubic root of 256742431 is about 635.5736490600.

The spelling of 256742431 in words is "two hundred fifty-six million, seven hundred forty-two thousand, four hundred thirty-one".