721436701 has 4 divisors (see below), whose sum is σ = 763874172. Its totient is φ = 678999232.

The previous prime is 721436687. The next prime is 721436711. The reversal of 721436701 is 107634127.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 438860601 + 282576100 = 20949^2 + 16810^2 .

It is a cyclic number.

It is not a de Polignac number, because 721436701 - 2⁹ = 721436189 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721436711) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21218710 + ... + 21218743.

It is an arithmetic number, because the mean of its divisors is an integer number (190968543).

Almost surely, 2^721436701 is an apocalyptic number.

It is an amenable number.

721436701 is a deficient number, since it is larger than the sum of its proper divisors (42437471).

721436701 is a wasteful number, since it uses less digits than its factorization.

721436701 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42437470.

The product of its (nonzero) digits is 7056, while the sum is 31.

The square root of 721436701 is about 26859.5737307948. The cubic root of 721436701 is about 896.8767049561.

The spelling of 721436701 in words is "seven hundred twenty-one million, four hundred thirty-six thousand, seven hundred one".