21134242091 has 2 divisors, whose sum is σ = 21134242092. Its totient is φ = 21134242090.

The previous prime is 21134242069. The next prime is 21134242097. The reversal of 21134242091 is 19024243112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21134242091 - 2⁶ = 21134242027 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (21134242097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10567121045 + 10567121046.

It is an arithmetic number, because the mean of its divisors is an integer number (10567121046).

Almost surely, 2^21134242091 is an apocalyptic number.

21134242091 is a deficient number, since it is larger than the sum of its proper divisors (1).

21134242091 is an equidigital number, since it uses as much as digits as its factorization.

21134242091 is an evil number, because the sum of its binary digits is even.

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

The spelling of 21134242091 in words is "twenty-one billion, one hundred thirty-four million, two hundred forty-two thousand, ninety-one".