31232121 has 4 divisors (see below), whose sum is σ = 41642832. Its totient is φ = 20821412.

The previous prime is 31232087. The next prime is 31232141. The reversal of 31232121 is 12123213.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 31232121 - 2⁹ = 31231609 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 31232121.

It is not an unprimeable number, because it can be changed into a prime (31232141) 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, 5205351 + ... + 5205356.

It is an arithmetic number, because the mean of its divisors is an integer number (10410708).

Almost surely, 2^31232121 is an apocalyptic number.

It is an amenable number.

31232121 is a deficient number, since it is larger than the sum of its proper divisors (10410711).

31232121 is a wasteful number, since it uses less digits than its factorization.

31232121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10410710.

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

The square root of 31232121 is about 5588.5705685801. The cubic root of 31232121 is about 314.9201813384.

Adding to 31232121 its reverse (12123213), we get a palindrome (43355334).

It can be divided in two parts, 3123212 and 1, that added together give a palindrome (3123213).

The spelling of 31232121 in words is "thirty-one million, two hundred thirty-two thousand, one hundred twenty-one".