721896 has 32 divisors (see below), whose sum is σ = 2063040. Its totient is φ = 206208.

The previous prime is 721891. The next prime is 721909. The reversal of 721896 is 698127.

It is a super-2 number, since 2×721896² = 1042267669632, which contains 22 as substring.

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

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 721896.

It is not an unprimeable number, because it can be changed into a prime (721891) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1981 + ... + 2316.

It is an arithmetic number, because the mean of its divisors is an integer number (64470).

2⁷²¹⁸⁹⁶ is an apocalyptic number.

It is an amenable number.

721896 is an abundant number, since it is smaller than the sum of its proper divisors (1341144).

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

721896 is a wasteful number, since it uses less digits than its factorization.

721896 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4313 (or 4309 counting only the distinct ones).

The product of its digits is 6048, while the sum is 33.

The square root of 721896 is about 849.6446315961. The cubic root of 721896 is about 89.7066995241.

The spelling of 721896 in words is "seven hundred twenty-one thousand, eight hundred ninety-six".