623009921 has 2 divisors, whose sum is σ = 623009922. Its totient is φ = 623009920.

The previous prime is 623009909. The next prime is 623009963. The reversal of 623009921 is 129900326.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 311875600 + 311134321 = 17660^2 + 17639^2 .

It is a cyclic number.

It is not a de Polignac number, because 623009921 - 2⁶ = 623009857 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (623009971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 311504960 + 311504961.

It is an arithmetic number, because the mean of its divisors is an integer number (311504961).

Almost surely, 2^623009921 is an apocalyptic number.

It is an amenable number.

623009921 is a deficient number, since it is larger than the sum of its proper divisors (1).

623009921 is an equidigital number, since it uses as much as digits as its factorization.

623009921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5832, while the sum is 32.

The square root of 623009921 is about 24960.1666861421. The cubic root of 623009921 is about 854.0795452125.

The spelling of 623009921 in words is "six hundred twenty-three million, nine thousand, nine hundred twenty-one".