101211220991 has 2 divisors, whose sum is σ = 101211220992. Its totient is φ = 101211220990.

The previous prime is 101211220967. The next prime is 101211221009. The reversal of 101211220991 is 199022112101.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 101211220991 - 2²⁶ = 101144112127 is a prime.

It is a super-2 number, since 2×101211220991² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (101211220921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50605610495 + 50605610496.

It is an arithmetic number, because the mean of its divisors is an integer number (50605610496).

Almost surely, 2^101211220991 is an apocalyptic number.

101211220991 is a deficient number, since it is larger than the sum of its proper divisors (1).

101211220991 is an equidigital number, since it uses as much as digits as its factorization.

101211220991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 29.

The spelling of 101211220991 in words is "one hundred one billion, two hundred eleven million, two hundred twenty thousand, nine hundred ninety-one".