72747778 has 8 divisors (see below), whose sum is σ = 109575180. Its totient is φ = 36222720.

The previous prime is 72747761. The next prime is 72747797. The reversal of 72747778 is 87774727.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 62204769 + 10543009 = 7887^2 + 3247^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 74983 + ... + 75946.

Almost surely, 2^72747778 is an apocalyptic number.

72747778 is a deficient number, since it is larger than the sum of its proper divisors (36827402).

72747778 is a wasteful number, since it uses less digits than its factorization.

72747778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 151172.

The product of its digits is 1075648, while the sum is 49.

The square root of 72747778 is about 8529.2307976745. The cubic root of 72747778 is about 417.4520302972.

The spelling of 72747778 in words is "seventy-two million, seven hundred forty-seven thousand, seven hundred seventy-eight".