724201661 has 2 divisors, whose sum is σ = 724201662. Its totient is φ = 724201660.

The previous prime is 724201619. The next prime is 724201693. The reversal of 724201661 is 166102427.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 697224025 + 26977636 = 26405^2 + 5194^2 .

It is a cyclic number.

It is not a de Polignac number, because 724201661 - 2²⁶ = 657092797 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (724201061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 362100830 + 362100831.

It is an arithmetic number, because the mean of its divisors is an integer number (362100831).

Almost surely, 2^724201661 is an apocalyptic number.

It is an amenable number.

724201661 is a deficient number, since it is larger than the sum of its proper divisors (1).

724201661 is an equidigital number, since it uses as much as digits as its factorization.

724201661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 724201661 is about 26910.9951692612. The cubic root of 724201661 is about 898.0210266024.

The spelling of 724201661 in words is "seven hundred twenty-four million, two hundred one thousand, six hundred sixty-one".