720215999 has 4 divisors (see below), whose sum is σ = 762581664. Its totient is φ = 677850336.

The previous prime is 720215981. The next prime is 720216011. The reversal of 720215999 is 999512027.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 720215999 - 2²⁸ = 451780543 is a prime.

It is a super-2 number, since 2×720215999² = 1037422170431136002, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (720215929) 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, 21182807 + ... + 21182840.

It is an arithmetic number, because the mean of its divisors is an integer number (190645416).

Almost surely, 2^720215999 is an apocalyptic number.

720215999 is a deficient number, since it is larger than the sum of its proper divisors (42365665).

720215999 is a wasteful number, since it uses less digits than its factorization.

720215999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42365664.

The product of its (nonzero) digits is 102060, while the sum is 44.

The square root of 720215999 is about 26836.8403319020. The cubic root of 720215999 is about 896.3705680302.

The spelling of 720215999 in words is "seven hundred twenty million, two hundred fifteen thousand, nine hundred ninety-nine".