20436121 has 8 divisors (see below), whose sum is σ = 21400704. Its totient is φ = 19477920.

The previous prime is 20436113. The next prime is 20436133. The reversal of 20436121 is 12163402.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20436121 - 2³ = 20436113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20436151) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5725 + ... + 8581.

It is an arithmetic number, because the mean of its divisors is an integer number (2675088).

Almost surely, 2^20436121 is an apocalyptic number.

It is an amenable number.

20436121 is a deficient number, since it is larger than the sum of its proper divisors (964583).

20436121 is a wasteful number, since it uses less digits than its factorization.

20436121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3191.

The product of its (nonzero) digits is 288, while the sum is 19.

The square root of 20436121 is about 4520.6328096849. The cubic root of 20436121 is about 273.4006158314.

Adding to 20436121 its reverse (12163402), we get a palindrome (32599523).

The spelling of 20436121 in words is "twenty million, four hundred thirty-six thousand, one hundred twenty-one".