21234013091 has 2 divisors, whose sum is σ = 21234013092. Its totient is φ = 21234013090.

The previous prime is 21234013069. The next prime is 21234013169. The reversal of 21234013091 is 19031043212.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21234013091 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21234013091.

It is not a weakly prime, because it can be changed into another prime (21234019091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10617006545 + 10617006546.

It is an arithmetic number, because the mean of its divisors is an integer number (10617006546).

Almost surely, 2^21234013091 is an apocalyptic number.

21234013091 is a deficient number, since it is larger than the sum of its proper divisors (1).

21234013091 is an equidigital number, since it uses as much as digits as its factorization.

21234013091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1296, while the sum is 26.

The spelling of 21234013091 in words is "twenty-one billion, two hundred thirty-four million, thirteen thousand, ninety-one".