21442312091 has 2 divisors, whose sum is σ = 21442312092. Its totient is φ = 21442312090.

The previous prime is 21442312057. The next prime is 21442312147. The reversal of 21442312091 is 19021324412.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21442312091 is a prime.

It is not a weakly prime, because it can be changed into another prime (21442342091) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10721156045 + 10721156046.

It is an arithmetic number, because the mean of its divisors is an integer number (10721156046).

Almost surely, 2^21442312091 is an apocalyptic number.

21442312091 is a deficient number, since it is larger than the sum of its proper divisors (1).

21442312091 is an equidigital number, since it uses as much as digits as its factorization.

21442312091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3456, while the sum is 29.

The spelling of 21442312091 in words is "twenty-one billion, four hundred forty-two million, three hundred twelve thousand, ninety-one".