921575231 has 2 divisors, whose sum is σ = 921575232. Its totient is φ = 921575230.

The previous prime is 921575189. The next prime is 921575233. The reversal of 921575231 is 132575129.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 921575231 - 2⁶ = 921575167 is a prime.

It is a super-2 number, since 2×921575231² = 1698601812785406722, which contains 22 as substring.

Together with 921575233, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 921575191 and 921575200.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (921575233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 460787615 + 460787616.

It is an arithmetic number, because the mean of its divisors is an integer number (460787616).

Almost surely, 2^921575231 is an apocalyptic number.

921575231 is a deficient number, since it is larger than the sum of its proper divisors (1).

921575231 is an equidigital number, since it uses as much as digits as its factorization.

921575231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18900, while the sum is 35.

The square root of 921575231 is about 30357.4575845870. The cubic root of 921575231 is about 973.1436010388.

The spelling of 921575231 in words is "nine hundred twenty-one million, five hundred seventy-five thousand, two hundred thirty-one".