20122121 has 4 divisors (see below), whose sum is σ = 21181200. Its totient is φ = 19063044.

The previous prime is 20122093. The next prime is 20122133. The reversal of 20122121 is 12122102.

It is a happy number.

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 20122121 - 2¹⁰ = 20121097 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20122621) 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, 529511 + ... + 529548.

It is an arithmetic number, because the mean of its divisors is an integer number (5295300).

Almost surely, 2^20122121 is an apocalyptic number.

It is an amenable number.

20122121 is a deficient number, since it is larger than the sum of its proper divisors (1059079).

20122121 is a wasteful number, since it uses less digits than its factorization.

20122121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1059078.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 20122121 is about 4485.7687189600. The cubic root of 20122121 is about 271.9931199601.

Adding to 20122121 its reverse (12122102), we get a palindrome (32244223).

It can be divided in two parts, 201 and 22121, that added together give a palindrome (22322).

The spelling of 20122121 in words is "twenty million, one hundred twenty-two thousand, one hundred twenty-one".