22031881 has 4 divisors (see below), whose sum is σ = 23327892. Its totient is φ = 20735872.

The previous prime is 22031873. The next prime is 22031899. The reversal of 22031881 is 18813022.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 18813022 = 2 ⋅9406511.

It can be written as a sum of positive squares in 2 ways, for example, as 8643600 + 13388281 = 2940^2 + 3659^2 .

It is a cyclic number.

It is not a de Polignac number, because 22031881 - 2³ = 22031873 is a prime.

It is a super-2 number, since 2×22031881² = 970807560796322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (22031831) 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, 647980 + ... + 648013.

It is an arithmetic number, because the mean of its divisors is an integer number (5831973).

Almost surely, 2^22031881 is an apocalyptic number.

It is an amenable number.

22031881 is a deficient number, since it is larger than the sum of its proper divisors (1296011).

22031881 is a wasteful number, since it uses less digits than its factorization.

22031881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1296010.

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 22031881 is about 4693.8130555019. The cubic root of 22031881 is about 280.3392189735.

The spelling of 22031881 in words is "twenty-two million, thirty-one thousand, eight hundred eighty-one".