72778605 has 8 divisors (see below), whose sum is σ = 116445792. Its totient is φ = 38815248.

The previous prime is 72778583. The next prime is 72778609. The reversal of 72778605 is 50687727.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 72778605 - 2⁷ = 72778477 is a prime.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72778609) 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 7 ways as a sum of consecutive naturals, for example, 2425939 + ... + 2425968.

It is an arithmetic number, because the mean of its divisors is an integer number (14555724).

Almost surely, 2^72778605 is an apocalyptic number.

It is an amenable number.

72778605 is a deficient number, since it is larger than the sum of its proper divisors (43667187).

72778605 is a wasteful number, since it uses less digits than its factorization.

72778605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4851915.

The product of its (nonzero) digits is 164640, while the sum is 42.

The square root of 72778605 is about 8531.0377446123. The cubic root of 72778605 is about 417.5109873165.

The spelling of 72778605 in words is "seventy-two million, seven hundred seventy-eight thousand, six hundred five".