72778723 has 4 divisors (see below), whose sum is σ = 72873648. Its totient is φ = 72683800.

The previous prime is 72778711. The next prime is 72778729. The reversal of 72778723 is 32787727.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 72778723 - 2²⁵ = 39224291 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 72778723.

It is not an unprimeable number, because it can be changed into a prime (72778729) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46303 + ... + 47848.

It is an arithmetic number, because the mean of its divisors is an integer number (18218412).

Almost surely, 2^72778723 is an apocalyptic number.

72778723 is a deficient number, since it is larger than the sum of its proper divisors (94925).

72778723 is an equidigital number, since it uses as much as digits as its factorization.

72778723 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 94924.

The product of its digits is 230496, while the sum is 43.

The square root of 72778723 is about 8531.0446605325. The cubic root of 72778723 is about 417.5112129609.

The spelling of 72778723 in words is "seventy-two million, seven hundred seventy-eight thousand, seven hundred twenty-three".