507663721 has 2 divisors, whose sum is σ = 507663722. Its totient is φ = 507663720.

The previous prime is 507663701. The next prime is 507663731. The reversal of 507663721 is 127366705.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 506250000 + 1413721 = 22500^2 + 1189^2 .

It is a cyclic number.

It is not a de Polignac number, because 507663721 - 2⁷ = 507663593 is a prime.

It is not a weakly prime, because it can be changed into another prime (507663701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 253831860 + 253831861.

It is an arithmetic number, because the mean of its divisors is an integer number (253831861).

Almost surely, 2^507663721 is an apocalyptic number.

It is an amenable number.

507663721 is a deficient number, since it is larger than the sum of its proper divisors (1).

507663721 is an equidigital number, since it uses as much as digits as its factorization.

507663721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 52920, while the sum is 37.

The square root of 507663721 is about 22531.3941202048. The cubic root of 507663721 is about 797.7351152768.

The spelling of 507663721 in words is "five hundred seven million, six hundred sixty-three thousand, seven hundred twenty-one".