72778616 has 16 divisors (see below), whose sum is σ = 138497640. Its totient is φ = 35845920.

The previous prime is 72778613. The next prime is 72778619. The reversal of 72778616 is 61687727.

It is an interprime number because it is at equal distance from previous prime (72778613) and next prime (72778619).

It is a Smith number, since the sum of its digits (44) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72778613) 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, 67355 + ... + 68426.

Almost surely, 2^72778616 is an apocalyptic number.

It is an amenable number.

72778616 is a deficient number, since it is larger than the sum of its proper divisors (65719024).

72778616 is a wasteful number, since it uses less digits than its factorization.

72778616 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135854 (or 135850 counting only the distinct ones).

The product of its digits is 197568, while the sum is 44.

The square root of 72778616 is about 8531.0383893170. The cubic root of 72778616 is about 417.5110083511.

It can be divided in two parts, 72 and 778616, that added together give a cube (778688 = 92³).

The spelling of 72778616 in words is "seventy-two million, seven hundred seventy-eight thousand, six hundred sixteen".