72805522 has 4 divisors (see below), whose sum is σ = 109208286. Its totient is φ = 36402760.

The previous prime is 72805507. The next prime is 72805553. The reversal of 72805522 is 22550827.

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

It can be written as a sum of positive squares in only one way, i.e., 65788321 + 7017201 = 8111^2 + 2649^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 18201379 + ... + 18201382.

Almost surely, 2^72805522 is an apocalyptic number.

72805522 is a deficient number, since it is larger than the sum of its proper divisors (36402764).

72805522 is a wasteful number, since it uses less digits than its factorization.

72805522 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36402763.

The product of its (nonzero) digits is 11200, while the sum is 31.

The square root of 72805522 is about 8532.6151911357. The cubic root of 72805522 is about 417.5624527990.

The spelling of 72805522 in words is "seventy-two million, eight hundred five thousand, five hundred twenty-two".