721713540 has 24 divisors (see below), whose sum is σ = 2020798080. Its totient is φ = 192456928.

The previous prime is 721713533. The next prime is 721713541. The reversal of 721713540 is 45317127.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 721713498 and 721713507.

It is not an unprimeable number, because it can be changed into a prime (721713541) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6014220 + ... + 6014339.

It is an arithmetic number, because the mean of its divisors is an integer number (84199920).

Almost surely, 2^721713540 is an apocalyptic number.

It is an amenable number.

721713540 is an abundant number, since it is smaller than the sum of its proper divisors (1299084540).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

721713540 is a wasteful number, since it uses less digits than its factorization.

721713540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12028571 (or 12028569 counting only the distinct ones).

The product of its (nonzero) digits is 5880, while the sum is 30.

The square root of 721713540 is about 26864.7266876103. The cubic root of 721713540 is about 896.9914106527.

The spelling of 721713540 in words is "seven hundred twenty-one million, seven hundred thirteen thousand, five hundred forty".