20313121 has 2 divisors, whose sum is σ = 20313122. Its totient is φ = 20313120.

The previous prime is 20313119. The next prime is 20313133. The reversal of 20313121 is 12131302.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19704721 + 608400 = 4439^2 + 780^2 .

It is a cyclic number.

It is not a de Polignac number, because 20313121 - 2¹ = 20313119 is a prime.

Together with 20313119, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20313421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10156560 + 10156561.

It is an arithmetic number, because the mean of its divisors is an integer number (10156561).

Almost surely, 2^20313121 is an apocalyptic number.

It is an amenable number.

20313121 is a deficient number, since it is larger than the sum of its proper divisors (1).

20313121 is an equidigital number, since it uses as much as digits as its factorization.

20313121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 20313121 is about 4507.0079875678. The cubic root of 20313121 is about 272.8510012702.

Adding to 20313121 its reverse (12131302), we get a palindrome (32444423).

The spelling of 20313121 in words is "twenty million, three hundred thirteen thousand, one hundred twenty-one".