72253121 has 4 divisors (see below), whose sum is σ = 72460500. Its totient is φ = 72045744.

The previous prime is 72253117. The next prime is 72253133. The reversal of 72253121 is 12135227.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12135227 = 13 ⋅933479.

It can be written as a sum of positive squares in 2 ways, for example, as 66912400 + 5340721 = 8180^2 + 2311^2 .

It is a cyclic number.

It is not a de Polignac number, because 72253121 - 2² = 72253117 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72253421) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 103166 + ... + 103863.

It is an arithmetic number, because the mean of its divisors is an integer number (18115125).

Almost surely, 2^72253121 is an apocalyptic number.

It is an amenable number.

72253121 is a deficient number, since it is larger than the sum of its proper divisors (207379).

72253121 is a wasteful number, since it uses less digits than its factorization.

72253121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 207378.

The product of its digits is 840, while the sum is 23.

The square root of 72253121 is about 8500.1835862527. The cubic root of 72253121 is about 416.5037063715.

Adding to 72253121 its reverse (12135227), we get a palindrome (84388348).

The spelling of 72253121 in words is "seventy-two million, two hundred fifty-three thousand, one hundred twenty-one".