721152 has 54 divisors (see below), whose sum is σ = 2085902. Its totient is φ = 239616.

The previous prime is 721141. The next prime is 721159. The reversal of 721152 is 251127.

It can be written as a sum of positive squares in only one way, i.e., 389376 + 331776 = 624^2 + 576^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721159) by changing a digit.

721152 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2148 + ... + 2460.

2⁷²¹¹⁵² is an apocalyptic number.

721152 is a gapful number since it is divisible by the number (72) 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 721152, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1042951).

721152 is an abundant number, since it is smaller than the sum of its proper divisors (1364750).

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

721152 is a wasteful number, since it uses less digits than its factorization.

721152 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 335 (or 318 counting only the distinct ones).

The product of its digits is 140, while the sum is 18.

The square root of 721152 is about 849.2066886218. The cubic root of 721152 is about 89.6758711102.

Adding to 721152 its reverse (251127), we get a palindrome (972279).

It can be divided in two parts, 72 and 1152, that multiplied together give a square (82944 = 288²).

The spelling of 721152 in words is "seven hundred twenty-one thousand, one hundred fifty-two".