211020091 has 2 divisors, whose sum is σ = 211020092. Its totient is φ = 211020090.

The previous prime is 211020079. The next prime is 211020107. The reversal of 211020091 is 190020112.

It is an a-pointer prime, because the next prime (211020107) can be obtained adding 211020091 to its sum of digits (16).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 211020091 - 2⁵ = 211020059 is a prime.

It is not a weakly prime, because it can be changed into another prime (211020001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105510045 + 105510046.

It is an arithmetic number, because the mean of its divisors is an integer number (105510046).

Almost surely, 2^211020091 is an apocalyptic number.

211020091 is a deficient number, since it is larger than the sum of its proper divisors (1).

211020091 is an equidigital number, since it uses as much as digits as its factorization.

211020091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 36, while the sum is 16.

The square root of 211020091 is about 14526.5305906125. The cubic root of 211020091 is about 595.3530762261.

It can be divided in two parts, 2110 and 20091, that added together give a square (22201 = 149²).

The spelling of 211020091 in words is "two hundred eleven million, twenty thousand, ninety-one".