721457152 has 104 divisors (see below), whose sum is σ = 1647177336. Its totient is φ = 312999936.

The previous prime is 721457119. The next prime is 721457183. The reversal of 721457152 is 251754127.

It can be written as a sum of positive squares in 4 ways, for example, as 79138816 + 642318336 = 8896^2 + 25344^2 .

It is a tau number, because it is divible by the number of its divisors (104).

It is a super-2 number, since 2×721457152² = 1041000844343902208, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (34).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 904818 + ... + 905614.

Almost surely, 2^721457152 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 721457152, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (823588668).

721457152 is an abundant number, since it is smaller than the sum of its proper divisors (925720184).

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

721457152 is a wasteful number, since it uses less digits than its factorization.

721457152 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 851 (or 829 counting only the distinct ones).

The product of its digits is 19600, while the sum is 34.

The square root of 721457152 is about 26859.9544303411. The cubic root of 721457152 is about 896.8851796438.

It can be divided in two parts, 72145 and 7152, that added together give a palindrome (79297).

The spelling of 721457152 in words is "seven hundred twenty-one million, four hundred fifty-seven thousand, one hundred fifty-two".