20901911 has 2 divisors, whose sum is σ = 20901912. Its totient is φ = 20901910.

The previous prime is 20901901. The next prime is 20901931. The reversal of 20901911 is 11910902.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20901911 - 2¹⁸ = 20639767 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20901901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10450955 + 10450956.

It is an arithmetic number, because the mean of its divisors is an integer number (10450956).

Almost surely, 2^20901911 is an apocalyptic number.

20901911 is a deficient number, since it is larger than the sum of its proper divisors (1).

20901911 is an equidigital number, since it uses as much as digits as its factorization.

20901911 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 162, while the sum is 23.

The square root of 20901911 is about 4571.8607809075. The cubic root of 20901911 is about 275.4621913568.

It can be divided in two parts, 20901 and 911, that added together give a palindrome (21812).

The spelling of 20901911 in words is "twenty million, nine hundred one thousand, nine hundred eleven".