20892121 has 2 divisors, whose sum is σ = 20892122. Its totient is φ = 20892120.

The previous prime is 20892101. The next prime is 20892143. The reversal of 20892121 is 12129802.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17338896 + 3553225 = 4164^2 + 1885^2 .

It is a cyclic number.

It is not a de Polignac number, because 20892121 - 2⁷ = 20891993 is a prime.

It is equal to p_1323574 and since 20892121 and 1323574 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (20892101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10446060 + 10446061.

It is an arithmetic number, because the mean of its divisors is an integer number (10446061).

Almost surely, 2^20892121 is an apocalyptic number.

It is an amenable number.

20892121 is a deficient number, since it is larger than the sum of its proper divisors (1).

20892121 is an equidigital number, since it uses as much as digits as its factorization.

20892121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 576, while the sum is 25.

The square root of 20892121 is about 4570.7899754856. The cubic root of 20892121 is about 275.4191778097.

It can be divided in two parts, 208 and 92121, that added together give a palindrome (92329).

The spelling of 20892121 in words is "twenty million, eight hundred ninety-two thousand, one hundred twenty-one".