721089897 has 16 divisors (see below), whose sum is σ = 1049917440. Its totient is φ = 436582800.

The previous prime is 721089877. The next prime is 721089907. The reversal of 721089897 is 798980127.

It is not a de Polignac number, because 721089897 - 2⁷ = 721089769 is a prime.

It is not an unprimeable number, because it can be changed into a prime (721089847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23772 + ... + 44802.

It is an arithmetic number, because the mean of its divisors is an integer number (65619840).

Almost surely, 2^721089897 is an apocalyptic number.

It is an amenable number.

721089897 is a deficient number, since it is larger than the sum of its proper divisors (328827543).

721089897 is a wasteful number, since it uses less digits than its factorization.

721089897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22084.

The product of its (nonzero) digits is 508032, while the sum is 51.

The square root of 721089897 is about 26853.1170816350. The cubic root of 721089897 is about 896.7329684916.

The spelling of 721089897 in words is "seven hundred twenty-one million, eighty-nine thousand, eight hundred ninety-seven".