523901921 has 2 divisors, whose sum is σ = 523901922. Its totient is φ = 523901920.

The previous prime is 523901909. The next prime is 523901923. The reversal of 523901921 is 129109325.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 318122896 + 205779025 = 17836^2 + 14345^2 .

It is a cyclic number.

It is not a de Polignac number, because 523901921 - 2⁶ = 523901857 is a prime.

Together with 523901923, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (523901923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 261950960 + 261950961.

It is an arithmetic number, because the mean of its divisors is an integer number (261950961).

Almost surely, 2^523901921 is an apocalyptic number.

It is an amenable number.

523901921 is a deficient number, since it is larger than the sum of its proper divisors (1).

523901921 is an equidigital number, since it uses as much as digits as its factorization.

523901921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4860, while the sum is 32.

The square root of 523901921 is about 22888.9038837599. The cubic root of 523901921 is about 806.1514948380.

The spelling of 523901921 in words is "five hundred twenty-three million, nine hundred one thousand, nine hundred twenty-one".