693222721 has 2 divisors, whose sum is σ = 693222722. Its totient is φ = 693222720.

The previous prime is 693222707. The next prime is 693222731. The reversal of 693222721 is 127222396.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 663629121 + 29593600 = 25761^2 + 5440^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-693222721 is a prime.

It is not a weakly prime, because it can be changed into another prime (693222731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 346611360 + 346611361.

It is an arithmetic number, because the mean of its divisors is an integer number (346611361).

Almost surely, 2^693222721 is an apocalyptic number.

It is an amenable number.

693222721 is a deficient number, since it is larger than the sum of its proper divisors (1).

693222721 is an equidigital number, since it uses as much as digits as its factorization.

693222721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18144, while the sum is 34.

The square root of 693222721 is about 26329.1230579372. The cubic root of 693222721 is about 885.0291928617.

The spelling of 693222721 in words is "six hundred ninety-three million, two hundred twenty-two thousand, seven hundred twenty-one".