721691460 has 288 divisors, whose sum is σ = 2598365952. Its totient is φ = 158745600.

The previous prime is 721691449. The next prime is 721691461. The reversal of 721691460 is 64196127.

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

It is not an unprimeable number, because it can be changed into a prime (721691461) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 6744727 + ... + 6744833.

It is an arithmetic number, because the mean of its divisors is an integer number (9022104).

Almost surely, 2^721691460 is an apocalyptic number.

721691460 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 721691460, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1299182976).

721691460 is an abundant number, since it is smaller than the sum of its proper divisors (1876674492).

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

721691460 is a wasteful number, since it uses less digits than its factorization.

721691460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 283 (or 278 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 721691460 is about 26864.3157366794. The cubic root of 721691460 is about 896.9822630841.

The spelling of 721691460 in words is "seven hundred twenty-one million, six hundred ninety-one thousand, four hundred sixty".