102111221101921 has 2 divisors, whose sum is σ = 102111221101922. Its totient is φ = 102111221101920.

The previous prime is 102111221101853. The next prime is 102111221101931. The reversal of 102111221101921 is 129101122111201.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 52743383351296 + 49367837750625 = 7262464^2 + 7026225^2 .

It is a cyclic number.

It is not a de Polignac number, because 102111221101921 - 2²⁹ = 102110684231009 is a prime.

It is not a weakly prime, because it can be changed into another prime (102111221101931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51055610550960 + 51055610550961.

It is an arithmetic number, because the mean of its divisors is an integer number (51055610550961).

Almost surely, 2^{102111221101921} is an apocalyptic number.

It is an amenable number.

102111221101921 is a deficient number, since it is larger than the sum of its proper divisors (1).

102111221101921 is an equidigital number, since it uses as much as digits as its factorization.

102111221101921 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 25.

The spelling of 102111221101921 in words is "one hundred two trillion, one hundred eleven billion, two hundred twenty-one million, one hundred one thousand, nine hundred twenty-one".