724201921 has 9 divisors (see below), whose sum is σ = 769794211. Its totient is φ = 681171232.

The previous prime is 724201883. The next prime is 724201937. The reversal of 724201921 is 129102427.

The square root of 724201921 is 26911.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 563825025 + 160376896 = 23745^2 + 12664^2 .

It is not a de Polignac number, because 724201921 - 2¹⁵ = 724169153 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 724201921.

It is not an unprimeable number, because it can be changed into a prime (724201421) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 456696 + ... + 458278.

Almost surely, 2^724201921 is an apocalyptic number.

724201921 is the 26911-st square number.

724201921 is the 13456-th centered octagonal number.

It is an amenable number.

724201921 is a deficient number, since it is larger than the sum of its proper divisors (45592290).

724201921 is an frugal number, since it uses more digits than its factorization.

724201921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3200 (or 1600 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 28.

The cubic root of 724201921 is about 898.0211340704.

The spelling of 724201921 in words is "seven hundred twenty-four million, two hundred one thousand, nine hundred twenty-one".