256515493 has 8 divisors (see below), whose sum is σ = 276375008. Its totient is φ = 236674224.

The previous prime is 256515461. The next prime is 256515509. The reversal of 256515493 is 394515652.

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 256515493 - 2⁵ = 256515461 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256915493) 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, 43330 + ... + 48892.

It is an arithmetic number, because the mean of its divisors is an integer number (34546876).

Almost surely, 2^256515493 is an apocalyptic number.

It is an amenable number.

256515493 is a deficient number, since it is larger than the sum of its proper divisors (19859515).

256515493 is a wasteful number, since it uses less digits than its factorization.

256515493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9123.

The product of its digits is 162000, while the sum is 40.

The square root of 256515493 is about 16016.1010548760. The cubic root of 256515493 is about 635.3863298982.

The spelling of 256515493 in words is "two hundred fifty-six million, five hundred fifteen thousand, four hundred ninety-three".