721474740 has 72 divisors (see below), whose sum is σ = 2501116800. Its totient is φ = 164908224.

The previous prime is 721474739. The next prime is 721474751. The reversal of 721474740 is 47474127.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 721474695 and 721474704.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 285040 + ... + 287559.

Almost surely, 2^721474740 is an apocalyptic number.

721474740 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

721474740 is an abundant number, since it is smaller than the sum of its proper divisors (1779642060).

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

721474740 is a wasteful number, since it uses less digits than its factorization.

721474740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 572621 (or 572616 counting only the distinct ones).

The product of its (nonzero) digits is 43904, while the sum is 36.

The square root of 721474740 is about 26860.2818302415. The cubic root of 721474740 is about 896.8924678052.

The spelling of 721474740 in words is "seven hundred twenty-one million, four hundred seventy-four thousand, seven hundred forty".