523972021 has 4 divisors (see below), whose sum is σ = 529059232. Its totient is φ = 518884812.

The previous prime is 523971997. The next prime is 523972067. The reversal of 523972021 is 120279325.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 523972021 - 2⁹ = 523971509 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 (523972081) 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, 2543451 + ... + 2543656.

It is an arithmetic number, because the mean of its divisors is an integer number (132264808).

Almost surely, 2^523972021 is an apocalyptic number.

It is an amenable number.

523972021 is a deficient number, since it is larger than the sum of its proper divisors (5087211).

523972021 is a wasteful number, since it uses less digits than its factorization.

523972021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5087210.

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 523972021 is about 22890.4351422161. The cubic root of 523972021 is about 806.1874485775.

The spelling of 523972021 in words is "five hundred twenty-three million, nine hundred seventy-two thousand, twenty-one".