213138839 has 2 divisors, whose sum is σ = 213138840. Its totient is φ = 213138838.

The previous prime is 213138817. The next prime is 213138853. The reversal of 213138839 is 938831312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 213138839 - 2¹² = 213134743 is a prime.

It is a Sophie Germain 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 (213138899) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106569419 + 106569420.

It is an arithmetic number, because the mean of its divisors is an integer number (106569420).

Almost surely, 2^213138839 is an apocalyptic number.

213138839 is a deficient number, since it is larger than the sum of its proper divisors (1).

213138839 is an equidigital number, since it uses as much as digits as its factorization.

213138839 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31104, while the sum is 38.

The square root of 213138839 is about 14599.2752902327. The cubic root of 213138839 is about 597.3389926988.

The spelling of 213138839 in words is "two hundred thirteen million, one hundred thirty-eight thousand, eight hundred thirty-nine".