72220072 has 8 divisors (see below), whose sum is σ = 135412650. Its totient is φ = 36110032.

The previous prime is 72220051. The next prime is 72220117. The reversal of 72220072 is 27002227.

It can be written as a sum of positive squares in only one way, i.e., 71470116 + 749956 = 8454^2 + 866^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4513747 + ... + 4513762.

Almost surely, 2^72220072 is an apocalyptic number.

72220072 is the 4543-rd centered heptagonal number.

It is an amenable number.

72220072 is a deficient number, since it is larger than the sum of its proper divisors (63192578).

72220072 is a wasteful number, since it uses less digits than its factorization.

72220072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9027515 (or 9027511 counting only the distinct ones).

The product of its (nonzero) digits is 784, while the sum is 22.

The square root of 72220072 is about 8498.2393470648. The cubic root of 72220072 is about 416.4401929432.

Adding to 72220072 its reverse (27002227), we get a palindrome (99222299).

The spelling of 72220072 in words is "seventy-two million, two hundred twenty thousand, seventy-two".