20312121 has 16 divisors (see below), whose sum is σ = 28607040. Its totient is φ = 12784320.

The previous prime is 20312113. The next prime is 20312137. The reversal of 20312121 is 12121302.

It is not a de Polignac number, because 20312121 - 2³ = 20312113 is a prime.

It is a super-3 number, since 3×20312121³ (a number of 23 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20312097 and 20312106.

It is not an unprimeable number, because it can be changed into a prime (20312111) 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 15 ways as a sum of consecutive naturals, for example, 25891 + ... + 26663.

It is an arithmetic number, because the mean of its divisors is an integer number (1787940).

Almost surely, 2^20312121 is an apocalyptic number.

It is an amenable number.

20312121 is a deficient number, since it is larger than the sum of its proper divisors (8294919).

20312121 is a wasteful number, since it uses less digits than its factorization.

20312121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1256.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 20312121 is about 4506.8970478590. The cubic root of 20312121 is about 272.8465237787.

Adding to 20312121 its reverse (12121302), we get a palindrome (32433423).

The spelling of 20312121 in words is "twenty million, three hundred twelve thousand, one hundred twenty-one".