721646452 has 6 divisors (see below), whose sum is σ = 1262881298. Its totient is φ = 360823224.

The previous prime is 721646449. The next prime is 721646461. The reversal of 721646452 is 254646127.

721646452 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 619312996 + 102333456 = 24886^2 + 10116^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 90205803 + ... + 90205810.

Almost surely, 2^721646452 is an apocalyptic number.

It is an amenable number.

721646452 is a deficient number, since it is larger than the sum of its proper divisors (541234846).

721646452 is a wasteful number, since it uses less digits than its factorization.

721646452 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 180411617 (or 180411615 counting only the distinct ones).

The product of its digits is 80640, while the sum is 37.

The square root of 721646452 is about 26863.4780324514. The cubic root of 721646452 is about 896.9636160494.

The spelling of 721646452 in words is "seven hundred twenty-one million, six hundred forty-six thousand, four hundred fifty-two".