721867065 has 16 divisors (see below), whose sum is σ = 1174564800. Its totient is φ = 378469952.

The previous prime is 721867051. The next prime is 721867067. The reversal of 721867065 is 560768127.

It is a cyclic number.

It is not a de Polignac number, because 721867065 - 2⁸ = 721866809 is a prime.

It is not an unprimeable number, because it can be changed into a prime (721867067) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 406950 + ... + 408719.

It is an arithmetic number, because the mean of its divisors is an integer number (73410300).

Almost surely, 2^721867065 is an apocalyptic number.

It is an amenable number.

721867065 is a deficient number, since it is larger than the sum of its proper divisors (452697735).

721867065 is a wasteful number, since it uses less digits than its factorization.

721867065 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 815736.

The product of its (nonzero) digits is 141120, while the sum is 42.

The square root of 721867065 is about 26867.5839070059. The cubic root of 721867065 is about 897.0550096824.

The spelling of 721867065 in words is "seven hundred twenty-one million, eight hundred sixty-seven thousand, sixty-five".