72165222 has 16 divisors (see below), whose sum is σ = 160367280. Its totient is φ = 24055056.

The previous prime is 72165131. The next prime is 72165229. The reversal of 72165222 is 22256127.

72165222 is a `hidden beast` number, since 7 + 2 + 1 + 652 + 2 + 2 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72165229) 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, 668143 + ... + 668250.

It is an arithmetic number, because the mean of its divisors is an integer number (10022955).

Almost surely, 2^72165222 is an apocalyptic number.

72165222 is an abundant number, since it is smaller than the sum of its proper divisors (88202058).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

72165222 is a wasteful number, since it uses less digits than its factorization.

72165222 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1336404 (or 1336398 counting only the distinct ones).

The product of its digits is 3360, while the sum is 27.

The square root of 72165222 is about 8495.0115950480. The cubic root of 72165222 is about 416.3347396667.

It can be divided in two parts, 72165 and 222, that multiplied together give a triangular number (16020630 = T₅₆₆₀).

The spelling of 72165222 in words is "seventy-two million, one hundred sixty-five thousand, two hundred twenty-two".