664553873 has 2 divisors, whose sum is σ = 664553874. Its totient is φ = 664553872.

The previous prime is 664553843. The next prime is 664553891. The reversal of 664553873 is 378355466.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 373919569 + 290634304 = 19337^2 + 17048^2 .

It is a cyclic number.

It is not a de Polignac number, because 664553873 - 2¹⁶ = 664488337 is a prime.

It is not a weakly prime, because it can be changed into another prime (664553843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332276936 + 332276937.

It is an arithmetic number, because the mean of its divisors is an integer number (332276937).

Almost surely, 2^664553873 is an apocalyptic number.

It is an amenable number.

664553873 is a deficient number, since it is larger than the sum of its proper divisors (1).

664553873 is an equidigital number, since it uses as much as digits as its factorization.

664553873 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1814400, while the sum is 47.

The square root of 664553873 is about 25778.9424336996. The cubic root of 664553873 is about 872.6566404863.

The spelling of 664553873 in words is "six hundred sixty-four million, five hundred fifty-three thousand, eight hundred seventy-three".