23311221199991 has 2 divisors, whose sum is σ = 23311221199992. Its totient is φ = 23311221199990.

The previous prime is 23311221199921. The next prime is 23311221200017. The reversal of 23311221199991 is 19999112211332.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-23311221199991 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (23311221199901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11655610599995 + 11655610599996.

It is an arithmetic number, because the mean of its divisors is an integer number (11655610599996).

Almost surely, 2^{23311221199991} is an apocalyptic number.

23311221199991 is a deficient number, since it is larger than the sum of its proper divisors (1).

23311221199991 is an equidigital number, since it uses as much as digits as its factorization.

23311221199991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 472392, while the sum is 53.

The spelling of 23311221199991 in words is "twenty-three trillion, three hundred eleven billion, two hundred twenty-one million, one hundred ninety-nine thousand, nine hundred ninety-one".