256424493 has 32 divisors (see below), whose sum is σ = 385652736. Its totient is φ = 150372288.

The previous prime is 256424479. The next prime is 256424501. The reversal of 256424493 is 394424652.

It is not a de Polignac number, because 256424493 - 2⁵ = 256424461 is a prime.

It is a super-2 number, since 2×256424493² = 131507041220614098, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256424473) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 436546 + ... + 437132.

It is an arithmetic number, because the mean of its divisors is an integer number (12051648).

Almost surely, 2^256424493 is an apocalyptic number.

256424493 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

256424493 is a deficient number, since it is larger than the sum of its proper divisors (129228243).

256424493 is a wasteful number, since it uses less digits than its factorization.

256424493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1113.

The product of its digits is 207360, while the sum is 39.

The square root of 256424493 is about 16013.2599117107. The cubic root of 256424493 is about 635.3111856460.

It can be divided in two parts, 25642 and 4493, that added together give a triangular number (30135 = T₂₄₅).

The spelling of 256424493 in words is "two hundred fifty-six million, four hundred twenty-four thousand, four hundred ninety-three".