21112111121137 has 2 divisors, whose sum is σ = 21112111121138. Its totient is φ = 21112111121136.

The previous prime is 21112111121089. The next prime is 21112111121183. The reversal of 21112111121137 is 73112111121112.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19318978552896 + 1793132568241 = 4395336^2 + 1339079^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21112111121137 is a prime.

It is not a weakly prime, because it can be changed into another prime (21112111121537) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10556055560568 + 10556055560569.

It is an arithmetic number, because the mean of its divisors is an integer number (10556055560569).

Almost surely, 2^{21112111121137} is an apocalyptic number.

It is an amenable number.

21112111121137 is a deficient number, since it is larger than the sum of its proper divisors (1).

21112111121137 is an equidigital number, since it uses as much as digits as its factorization.

21112111121137 is an evil number, because the sum of its binary digits is even.

The product of its digits is 168, while the sum is 25.

Subtracting from 21112111121137 its sum of digits (25), we obtain a palindrome (21112111121112).

Adding to 21112111121137 its reverse (73112111121112), we get a palindrome (94224222242249).

The spelling of 21112111121137 in words is "twenty-one trillion, one hundred twelve billion, one hundred eleven million, one hundred twenty-one thousand, one hundred thirty-seven".