720779893 has 4 divisors (see below), whose sum is σ = 723345228. Its totient is φ = 718214560.

The previous prime is 720779863. The next prime is 720779909. The reversal of 720779893 is 398977027.

It is a happy number.

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 626651089 + 94128804 = 25033^2 + 9702^2 .

It is a cyclic number.

It is not a de Polignac number, because 720779893 - 2¹⁷ = 720648821 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 720779893.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (720779863) 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, 1282246 + ... + 1282807.

It is an arithmetic number, because the mean of its divisors is an integer number (180836307).

Almost surely, 2^720779893 is an apocalyptic number.

It is an amenable number.

720779893 is a deficient number, since it is larger than the sum of its proper divisors (2565335).

720779893 is a wasteful number, since it uses less digits than its factorization.

720779893 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2565334.

The product of its (nonzero) digits is 1333584, while the sum is 52.

The square root of 720779893 is about 26847.3442448224. The cubic root of 720779893 is about 896.6044451480.

The spelling of 720779893 in words is "seven hundred twenty million, seven hundred seventy-nine thousand, eight hundred ninety-three".