801720418 has 4 divisors (see below), whose sum is σ = 1202580630. Its totient is φ = 400860208.

The previous prime is 801720389. The next prime is 801720421. The reversal of 801720418 is 814027108.

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., 699972849 + 101747569 = 26457^2 + 10087^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 801720418.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200430103 + ... + 200430106.

Almost surely, 2^801720418 is an apocalyptic number.

801720418 is a deficient number, since it is larger than the sum of its proper divisors (400860212).

801720418 is a wasteful number, since it uses less digits than its factorization.

801720418 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 400860211.

The product of its (nonzero) digits is 3584, while the sum is 31.

The square root of 801720418 is about 28314.6678949268. The cubic root of 801720418 is about 928.9827463471.

The spelling of 801720418 in words is "eight hundred one million, seven hundred twenty thousand, four hundred eighteen".