21376339 has 2 divisors, whose sum is σ = 21376340. Its totient is φ = 21376338.

The previous prime is 21376321. The next prime is 21376351. The reversal of 21376339 is 93367312.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21376339 is a prime.

It is not a weakly prime, because it can be changed into another prime (21376319) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10688169 + 10688170.

It is an arithmetic number, because the mean of its divisors is an integer number (10688170).

Almost surely, 2^21376339 is an apocalyptic number.

21376339 is a deficient number, since it is larger than the sum of its proper divisors (1).

21376339 is an equidigital number, since it uses as much as digits as its factorization.

21376339 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20412, while the sum is 34.

The square root of 21376339 is about 4623.4553096142. The cubic root of 21376339 is about 277.5307500486.

The spelling of 21376339 in words is "twenty-one million, three hundred seventy-six thousand, three hundred thirty-nine".