212220091 has 2 divisors, whose sum is σ = 212220092. Its totient is φ = 212220090.

The previous prime is 212220083. The next prime is 212220097. The reversal of 212220091 is 190022212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 212220091 - 2³ = 212220083 is a prime.

It is not a weakly prime, because it can be changed into another prime (212220097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106110045 + 106110046.

It is an arithmetic number, because the mean of its divisors is an integer number (106110046).

Almost surely, 2^212220091 is an apocalyptic number.

212220091 is a deficient number, since it is larger than the sum of its proper divisors (1).

212220091 is an equidigital number, since it uses as much as digits as its factorization.

212220091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 212220091 is about 14567.7757739471. The cubic root of 212220091 is about 596.4794677489.

The spelling of 212220091 in words is "two hundred twelve million, two hundred twenty thousand, ninety-one".