72778739 has 16 divisors (see below), whose sum is σ = 83185920. Its totient is φ = 63027360.

The previous prime is 72778729. The next prime is 72778807. The reversal of 72778739 is 93787727.

It is not a de Polignac number, because 72778739 - 2¹² = 72774643 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72778709) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 87377 + ... + 88205.

It is an arithmetic number, because the mean of its divisors is an integer number (5199120).

Almost surely, 2^72778739 is an apocalyptic number.

72778739 is a deficient number, since it is larger than the sum of its proper divisors (10407181).

72778739 is a wasteful number, since it uses less digits than its factorization.

72778739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1210.

The product of its digits is 1037232, while the sum is 50.

The square root of 72778739 is about 8531.0455982840. The cubic root of 72778739 is about 417.5112435568.

The spelling of 72778739 in words is "seventy-two million, seven hundred seventy-eight thousand, seven hundred thirty-nine".