21033310091 has 2 divisors, whose sum is σ = 21033310092. Its totient is φ = 21033310090.

The previous prime is 21033310057. The next prime is 21033310127. The reversal of 21033310091 is 19001333012.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21033310091 is a prime.

It is not a weakly prime, because it can be changed into another prime (21033340091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10516655045 + 10516655046.

It is an arithmetic number, because the mean of its divisors is an integer number (10516655046).

Almost surely, 2^21033310091 is an apocalyptic number.

21033310091 is a deficient number, since it is larger than the sum of its proper divisors (1).

21033310091 is an equidigital number, since it uses as much as digits as its factorization.

21033310091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 486, while the sum is 23.

The spelling of 21033310091 in words is "twenty-one billion, thirty-three million, three hundred ten thousand, ninety-one".