202121021121091 has 2 divisors, whose sum is σ = 202121021121092. Its totient is φ = 202121021121090.

The previous prime is 202121021121077. The next prime is 202121021121109. The reversal of 202121021121091 is 190121120121202.

Together with next prime (202121021121109) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 202121021121091 - 2³³ = 202112431186499 is a prime.

It is not a weakly prime, because it can be changed into another prime (202121021122091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 101060510560545 + 101060510560546.

It is an arithmetic number, because the mean of its divisors is an integer number (101060510560546).

Almost surely, 2^{202121021121091} is an apocalyptic number.

202121021121091 is a deficient number, since it is larger than the sum of its proper divisors (1).

202121021121091 is an equidigital number, since it uses as much as digits as its factorization.

202121021121091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 288, while the sum is 25.

Adding to 202121021121091 its reverse (190121120121202), we get a palindrome (392242141242293).

The spelling of 202121021121091 in words is "two hundred two trillion, one hundred twenty-one billion, twenty-one million, one hundred twenty-one thousand, ninety-one".