21367139 has 2 divisors, whose sum is σ = 21367140. Its totient is φ = 21367138.

The previous prime is 21367127. The next prime is 21367163. The reversal of 21367139 is 93176312.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21367139 - 2⁴ = 21367123 is a prime.

It is a super-3 number, since 3×21367139³ (a number of 23 digits) contains 333 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21367169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10683569 + 10683570.

It is an arithmetic number, because the mean of its divisors is an integer number (10683570).

Almost surely, 2^21367139 is an apocalyptic number.

21367139 is a deficient number, since it is larger than the sum of its proper divisors (1).

21367139 is an equidigital number, since it uses as much as digits as its factorization.

21367139 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6804, while the sum is 32.

The square root of 21367139 is about 4622.4602756541. The cubic root of 21367139 is about 277.4909295523.

The spelling of 21367139 in words is "twenty-one million, three hundred sixty-seven thousand, one hundred thirty-nine".