720644402 has 4 divisors (see below), whose sum is σ = 1080966606. Its totient is φ = 360322200.

The previous prime is 720644389. The next prime is 720644447. The reversal of 720644402 is 204446027.

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

It can be written as a sum of positive squares in only one way, i.e., 720331921 + 312481 = 26839^2 + 559^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 180161099 + ... + 180161102.

Almost surely, 2^720644402 is an apocalyptic number.

720644402 is a deficient number, since it is larger than the sum of its proper divisors (360322204).

720644402 is a wasteful number, since it uses less digits than its factorization.

720644402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 360322203.

The product of its (nonzero) digits is 10752, while the sum is 29.

The square root of 720644402 is about 26844.8207667699. The cubic root of 720644402 is about 896.5482608922.

The spelling of 720644402 in words is "seven hundred twenty million, six hundred forty-four thousand, four hundred two".