72022121 has 4 divisors (see below), whose sum is σ = 72054612. Its totient is φ = 71989632.

The previous prime is 72022079. The next prime is 72022123. The reversal of 72022121 is 12122027.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12122027 = 227 ⋅53401.

It can be written as a sum of positive squares in 2 ways, for example, as 1125721 + 70896400 = 1061^2 + 8420^2 .

It is a cyclic number.

It is not a de Polignac number, because 72022121 - 2⁶ = 72022057 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 72022121.

It is not an unprimeable number, because it can be changed into a prime (72022123) 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 3 ways as a sum of consecutive naturals, for example, 12656 + ... + 17441.

It is an arithmetic number, because the mean of its divisors is an integer number (18013653).

Almost surely, 2^72022121 is an apocalyptic number.

It is an amenable number.

72022121 is a deficient number, since it is larger than the sum of its proper divisors (32491).

72022121 is a wasteful number, since it uses less digits than its factorization.

72022121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32490.

The product of its (nonzero) digits is 112, while the sum is 17.

The square root of 72022121 is about 8486.5847665595. The cubic root of 72022121 is about 416.0593653722.

Adding to 72022121 its reverse (12122027), we get a palindrome (84144148).

The spelling of 72022121 in words is "seventy-two million, twenty-two thousand, one hundred twenty-one".