72855778 has 16 divisors (see below), whose sum is σ = 116564184. Its totient is φ = 34032640.

The previous prime is 72855767. The next prime is 72855779. The reversal of 72855778 is 87755827.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 71014329 + 1841449 = 8427^2 + 1357^2 .

It is not an unprimeable number, because it can be changed into a prime (72855779) 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, 3163 + ... + 12478.

Almost surely, 2^72855778 is an apocalyptic number.

72855778 is a deficient number, since it is larger than the sum of its proper divisors (43708406).

72855778 is a wasteful number, since it uses less digits than its factorization.

72855778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15797.

The product of its digits is 1097600, while the sum is 49.

The square root of 72855778 is about 8535.5596184433. The cubic root of 72855778 is about 417.6585086631.

Adding to 72855778 its sum of digits (49), we get a palindrome (72855827).

The spelling of 72855778 in words is "seventy-two million, eight hundred fifty-five thousand, seven hundred seventy-eight".