21694133 has 2 divisors, whose sum is σ = 21694134. Its totient is φ = 21694132.

The previous prime is 21694069. The next prime is 21694139. The reversal of 21694133 is 33149612.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20729809 + 964324 = 4553^2 + 982^2 .

It is a cyclic number.

It is not a de Polignac number, because 21694133 - 2⁶ = 21694069 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21694096 and 21694105.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21694139) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10847066 + 10847067.

It is an arithmetic number, because the mean of its divisors is an integer number (10847067).

Almost surely, 2^21694133 is an apocalyptic number.

It is an amenable number.

21694133 is a deficient number, since it is larger than the sum of its proper divisors (1).

21694133 is an equidigital number, since it uses as much as digits as its factorization.

21694133 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3888, while the sum is 29.

The square root of 21694133 is about 4657.6961042988. The cubic root of 21694133 is about 278.8993054832.

It can be divided in two parts, 216 and 94133, that added together give a palindrome (94349).

The spelling of 21694133 in words is "twenty-one million, six hundred ninety-four thousand, one hundred thirty-three".