720007778 has 16 divisors (see below), whose sum is σ = 1287964800. Its totient is φ = 295158336.

The previous prime is 720007763. The next prime is 720007789. The reversal of 720007778 is 877700027.

720007778 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×720007778² = 1036822400760994568, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1117703 + ... + 1118346.

It is an arithmetic number, because the mean of its divisors is an integer number (80497800).

Almost surely, 2^720007778 is an apocalyptic number.

720007778 is a deficient number, since it is larger than the sum of its proper divisors (567957022).

720007778 is a wasteful number, since it uses less digits than its factorization.

720007778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2236081.

The product of its (nonzero) digits is 38416, while the sum is 38.

The square root of 720007778 is about 26832.9606640788. The cubic root of 720007778 is about 896.2841767411.

The spelling of 720007778 in words is "seven hundred twenty million, seven thousand, seven hundred seventy-eight".