21337109 has 2 divisors, whose sum is σ = 21337110. Its totient is φ = 21337108.

The previous prime is 21337103. The next prime is 21337117. The reversal of 21337109 is 90173312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20566225 + 770884 = 4535^2 + 878^2 .

It is a cyclic number.

It is not a de Polignac number, because 21337109 - 2⁴ = 21337093 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21337103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10668554 + 10668555.

It is an arithmetic number, because the mean of its divisors is an integer number (10668555).

Almost surely, 2^21337109 is an apocalyptic number.

It is an amenable number.

21337109 is a deficient number, since it is larger than the sum of its proper divisors (1).

21337109 is an equidigital number, since it uses as much as digits as its factorization.

21337109 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1134, while the sum is 26.

The square root of 21337109 is about 4619.2108633402. The cubic root of 21337109 is about 277.3608706567.

The spelling of 21337109 in words is "twenty-one million, three hundred thirty-seven thousand, one hundred nine".