722647891 has 8 divisors (see below), whose sum is σ = 826053120. Its totient is φ = 619285128.

The previous prime is 722647867. The next prime is 722647903. The reversal of 722647891 is 198746227.

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

It is a de Polignac number, because none of the positive numbers 2^k-722647891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (722657891) 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, 45990 + ... + 59668.

It is an arithmetic number, because the mean of its divisors is an integer number (103256640).

Almost surely, 2^722647891 is an apocalyptic number.

722647891 is a deficient number, since it is larger than the sum of its proper divisors (103405229).

722647891 is a wasteful number, since it uses less digits than its factorization.

722647891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21233.

The product of its digits is 338688, while the sum is 46.

The square root of 722647891 is about 26882.1109848166. The cubic root of 722647891 is about 897.3783339756.

The spelling of 722647891 in words is "seven hundred twenty-two million, six hundred forty-seven thousand, eight hundred ninety-one".