623872009 has 2 divisors, whose sum is σ = 623872010. Its totient is φ = 623872008.

The previous prime is 623871979. The next prime is 623872021. The reversal of 623872009 is 900278326.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 395015625 + 228856384 = 19875^2 + 15128^2 .

It is a cyclic number.

It is not a de Polignac number, because 623872009 - 2⁷ = 623871881 is a prime.

It is a super-2 number, since 2×623872009² = 778432567227392162, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (623872609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 311936004 + 311936005.

It is an arithmetic number, because the mean of its divisors is an integer number (311936005).

Almost surely, 2^623872009 is an apocalyptic number.

It is an amenable number.

623872009 is a deficient number, since it is larger than the sum of its proper divisors (1).

623872009 is an equidigital number, since it uses as much as digits as its factorization.

623872009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36288, while the sum is 37.

The square root of 623872009 is about 24977.4299918947. The cubic root of 623872009 is about 854.4733069324.

The spelling of 623872009 in words is "six hundred twenty-three million, eight hundred seventy-two thousand, nine".