31222131 has 4 divisors (see below), whose sum is σ = 41629512. Its totient is φ = 20814752.

The previous prime is 31222129. The next prime is 31222133. The reversal of 31222131 is 13122213.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (31222129) and next prime (31222133).

It is a cyclic number.

It is not a de Polignac number, because 31222131 - 2¹ = 31222129 is a prime.

It is a super-2 number, since 2×31222131² = 1949642928362322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 31222131.

It is not an unprimeable number, because it can be changed into a prime (31222133) 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, 5203686 + ... + 5203691.

It is an arithmetic number, because the mean of its divisors is an integer number (10407378).

Almost surely, 2^31222131 is an apocalyptic number.

31222131 is a deficient number, since it is larger than the sum of its proper divisors (10407381).

31222131 is a wasteful number, since it uses less digits than its factorization.

31222131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10407380.

The product of its digits is 72, while the sum is 15.

The square root of 31222131 is about 5587.6767086151. The cubic root of 31222131 is about 314.8866006528.

Adding to 31222131 its reverse (13122213), we get a palindrome (44344344).

It can be divided in two parts, 3122 and 2131, that added together give a triangular number (5253 = T₁₀₂).

The spelling of 31222131 in words is "thirty-one million, two hundred twenty-two thousand, one hundred thirty-one".