72122881 has 4 divisors (see below), whose sum is σ = 72140500. Its totient is φ = 72105264.

The previous prime is 72122867. The next prime is 72122893. The reversal of 72122881 is 18822127.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18822127 = 149 ⋅126323.

It can be written as a sum of positive squares in 2 ways, for example, as 11282881 + 60840000 = 3359^2 + 7800^2 .

It is a cyclic number.

It is not a de Polignac number, because 72122881 - 2⁵ = 72122849 is a prime.

It is a super-2 number, since 2×72122881² = 10403419927480322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72122851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 895 + ... + 12043.

It is an arithmetic number, because the mean of its divisors is an integer number (18035125).

Almost surely, 2^72122881 is an apocalyptic number.

It is an amenable number.

72122881 is a deficient number, since it is larger than the sum of its proper divisors (17619).

72122881 is a wasteful number, since it uses less digits than its factorization.

72122881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17618.

The product of its digits is 3584, while the sum is 31.

The square root of 72122881 is about 8492.5191197901. The cubic root of 72122881 is about 416.2532993393.

The spelling of 72122881 in words is "seventy-two million, one hundred twenty-two thousand, eight hundred eighty-one".