21834691 has 2 divisors, whose sum is σ = 21834692. Its totient is φ = 21834690.

The previous prime is 21834679. The next prime is 21834707. The reversal of 21834691 is 19643812.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21834691 is a prime.

It is not a weakly prime, because it can be changed into another prime (21834601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10917345 + 10917346.

It is an arithmetic number, because the mean of its divisors is an integer number (10917346).

Almost surely, 2^21834691 is an apocalyptic number.

21834691 is a deficient number, since it is larger than the sum of its proper divisors (1).

21834691 is an equidigital number, since it uses as much as digits as its factorization.

21834691 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 10368, while the sum is 34.

The square root of 21834691 is about 4672.7605331324. The cubic root of 21834691 is about 279.5003461540.

The spelling of 21834691 in words is "twenty-one million, eight hundred thirty-four thousand, six hundred ninety-one".