724505521 has 12 divisors (see below), whose sum is σ = 754331292. Its totient is φ = 695812544.

The previous prime is 724505491. The next prime is 724505531. The reversal of 724505521 is 125505427.

It can be written as a sum of positive squares in 6 ways, for example, as 101304225 + 623201296 = 10065^2 + 24964^2 .

It is not a de Polignac number, because 724505521 - 2⁷ = 724505393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (724505531) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 163491 + ... + 167863.

It is an arithmetic number, because the mean of its divisors is an integer number (62860941).

Almost surely, 2^724505521 is an apocalyptic number.

It is an amenable number.

724505521 is a deficient number, since it is larger than the sum of its proper divisors (29825771).

724505521 is a wasteful number, since it uses less digits than its factorization.

724505521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4628 (or 4599 counting only the distinct ones).

The product of its (nonzero) digits is 14000, while the sum is 31.

The square root of 724505521 is about 26916.6402249612. The cubic root of 724505521 is about 898.1466060411.

The spelling of 724505521 in words is "seven hundred twenty-four million, five hundred five thousand, five hundred twenty-one".