21111201222031 has 2 divisors, whose sum is σ = 21111201222032. Its totient is φ = 21111201222030.

The previous prime is 21111201221989. The next prime is 21111201222049. The reversal of 21111201222031 is 13022210211112.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21111201222031 is a prime.

It is a super-2 number, since 2×21111201222031² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21111201222071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10555600611015 + 10555600611016.

It is an arithmetic number, because the mean of its divisors is an integer number (10555600611016).

Almost surely, 2^{21111201222031} is an apocalyptic number.

21111201222031 is a deficient number, since it is larger than the sum of its proper divisors (1).

21111201222031 is an equidigital number, since it uses as much as digits as its factorization.

21111201222031 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 19.

Adding to 21111201222031 its reverse (13022210211112), we get a palindrome (34133411433143).

The spelling of 21111201222031 in words is "twenty-one trillion, one hundred eleven billion, two hundred one million, two hundred twenty-two thousand, thirty-one".