721244881 has 4 divisors (see below), whose sum is σ = 824279872. Its totient is φ = 618209892.

The previous prime is 721244869. The next prime is 721244897. The reversal of 721244881 is 188442127.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 721244881 - 2⁷ = 721244753 is a prime.

It is a super-2 number, since 2×721244881² = 1040388356737408322, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 721244881.

It is not an unprimeable number, because it can be changed into a prime (721244861) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 51517485 + ... + 51517498.

It is an arithmetic number, because the mean of its divisors is an integer number (206069968).

Almost surely, 2^721244881 is an apocalyptic number.

It is an amenable number.

721244881 is a deficient number, since it is larger than the sum of its proper divisors (103034991).

721244881 is a wasteful number, since it uses less digits than its factorization.

721244881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103034990.

The product of its digits is 28672, while the sum is 37.

The square root of 721244881 is about 26856.0026995828. The cubic root of 721244881 is about 896.7972088899.

The spelling of 721244881 in words is "seven hundred twenty-one million, two hundred forty-four thousand, eight hundred eighty-one".