21011101101157 has 2 divisors, whose sum is σ = 21011101101158. Its totient is φ = 21011101101156.

The previous prime is 21011101101127. The next prime is 21011101101257. The reversal of 21011101101157 is 75110110111012.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20083743657121 + 927357444036 = 4481489^2 + 962994^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21011101101157 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21011101101127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10505550550578 + 10505550550579.

It is an arithmetic number, because the mean of its divisors is an integer number (10505550550579).

Almost surely, 2^{21011101101157} is an apocalyptic number.

It is an amenable number.

21011101101157 is a deficient number, since it is larger than the sum of its proper divisors (1).

21011101101157 is an equidigital number, since it uses as much as digits as its factorization.

21011101101157 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 70, while the sum is 22.

Adding to 21011101101157 its reverse (75110110111012), we get a palindrome (96121211212169).

The spelling of 21011101101157 in words is "twenty-one trillion, eleven billion, one hundred one million, one hundred one thousand, one hundred fifty-seven".