202120091 has 2 divisors, whose sum is σ = 202120092. Its totient is φ = 202120090.

The previous prime is 202119989. The next prime is 202120099. The reversal of 202120091 is 190021202.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-202120091 is a prime.

It is not a weakly prime, because it can be changed into another prime (202120099) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 101060045 + 101060046.

It is an arithmetic number, because the mean of its divisors is an integer number (101060046).

Almost surely, 2^202120091 is an apocalyptic number.

202120091 is a deficient number, since it is larger than the sum of its proper divisors (1).

202120091 is an equidigital number, since it uses as much as digits as its factorization.

202120091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 202120091 is about 14216.8945624563. The cubic root of 202120091 is about 586.8626833304.

Adding to 202120091 its reverse (190021202), we get a palindrome (392141293).

The spelling of 202120091 in words is "two hundred two million, one hundred twenty thousand, ninety-one".