521256423 has 4 divisors (see below), whose sum is σ = 695008568. Its totient is φ = 347504280.

The previous prime is 521256419. The next prime is 521256443. The reversal of 521256423 is 324652125.

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

It is not a de Polignac number, because 521256423 - 2² = 521256419 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 (521256443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 86876068 + ... + 86876073.

It is an arithmetic number, because the mean of its divisors is an integer number (173752142).

Almost surely, 2^521256423 is an apocalyptic number.

521256423 is a deficient number, since it is larger than the sum of its proper divisors (173752145).

521256423 is a wasteful number, since it uses less digits than its factorization.

521256423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173752144.

The product of its digits is 14400, while the sum is 30.

The square root of 521256423 is about 22831.0407778533. The cubic root of 521256423 is about 804.7922887833.

The spelling of 521256423 in words is "five hundred twenty-one million, two hundred fifty-six thousand, four hundred twenty-three".