72778877816 has 32 divisors (see below), whose sum is σ = 141577476480. Its totient is φ = 35036803200.

The previous prime is 72778877813. The next prime is 72778877819. The reversal of 72778877816 is 61877887727.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (72778877813) and next prime (72778877819).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72778877813) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 695975 + ... + 793686.

It is an arithmetic number, because the mean of its divisors is an integer number (4424296140).

Almost surely, 2^72778877816 is an apocalyptic number.

It is an amenable number.

72778877816 is a deficient number, since it is larger than the sum of its proper divisors (68798598664).

72778877816 is a wasteful number, since it uses less digits than its factorization.

72778877816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1489895 (or 1489891 counting only the distinct ones).

The product of its digits is 103262208, while the sum is 68.

The spelling of 72778877816 in words is "seventy-two billion, seven hundred seventy-eight million, eight hundred seventy-seven thousand, eight hundred sixteen".