72778679 has 2 divisors, whose sum is σ = 72778680. Its totient is φ = 72778678.

The previous prime is 72778663. The next prime is 72778709. The reversal of 72778679 is 97687727.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 72778679 - 2⁴ = 72778663 is a prime.

It is a super-2 number, since 2×72778679² = 10593472233970082, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 72778679.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72778609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36389339 + 36389340.

It is an arithmetic number, because the mean of its divisors is an integer number (36389340).

Almost surely, 2^72778679 is an apocalyptic number.

72778679 is a deficient number, since it is larger than the sum of its proper divisors (1).

72778679 is an equidigital number, since it uses as much as digits as its factorization.

72778679 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2074464, while the sum is 53.

The square root of 72778679 is about 8531.0420817155. The cubic root of 72778679 is about 417.5111288224.

The spelling of 72778679 in words is "seventy-two million, seven hundred seventy-eight thousand, six hundred seventy-nine".