721039697 has 8 divisors (see below), whose sum is σ = 824437056. Its totient is φ = 617740272.

The previous prime is 721039691. The next prime is 721039699. The reversal of 721039697 is 796930127.

It is a happy number.

721039697 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 721039697 - 2⁴ = 721039681 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (721039691) 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, 7958 + ... + 38799.

It is an arithmetic number, because the mean of its divisors is an integer number (103054632).

Almost surely, 2^721039697 is an apocalyptic number.

It is an amenable number.

721039697 is a deficient number, since it is larger than the sum of its proper divisors (103397359).

721039697 is a wasteful number, since it uses less digits than its factorization.

721039697 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48967.

The product of its (nonzero) digits is 142884, while the sum is 44.

The square root of 721039697 is about 26852.1823507885. The cubic root of 721039697 is about 896.7121587701.

The spelling of 721039697 in words is "seven hundred twenty-one million, thirty-nine thousand, six hundred ninety-seven".