721432 has 16 divisors (see below), whose sum is σ = 1396800. Its totient is φ = 348960.

The previous prime is 721397. The next prime is 721439. The reversal of 721432 is 234127.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721439) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1207 + ... + 1702.

It is an arithmetic number, because the mean of its divisors is an integer number (87300).

2⁷²¹⁴³² is an apocalyptic number.

It is an amenable number.

721432 is a deficient number, since it is larger than the sum of its proper divisors (675368).

721432 is a wasteful number, since it uses less digits than its factorization.

721432 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2946 (or 2942 counting only the distinct ones).

The product of its digits is 336, while the sum is 19.

The square root of 721432 is about 849.3715323697. The cubic root of 721432 is about 89.6874756887.

Adding to 721432 its reverse (234127), we get a palindrome (955559).

The spelling of 721432 in words is "seven hundred twenty-one thousand, four hundred thirty-two".