213856739 has 2 divisors, whose sum is σ = 213856740. Its totient is φ = 213856738.

The previous prime is 213856717. The next prime is 213856793. The reversal of 213856739 is 937658312.

Together with next prime (213856793) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-213856739 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 213856739.

It is not a weakly prime, because it can be changed into another prime (213855739) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106928369 + 106928370.

It is an arithmetic number, because the mean of its divisors is an integer number (106928370).

Almost surely, 2^213856739 is an apocalyptic number.

213856739 is a deficient number, since it is larger than the sum of its proper divisors (1).

213856739 is an equidigital number, since it uses as much as digits as its factorization.

213856739 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 272160, while the sum is 44.

The square root of 213856739 is about 14623.8414583857. The cubic root of 213856739 is about 598.0088989105.

The spelling of 213856739 in words is "two hundred thirteen million, eight hundred fifty-six thousand, seven hundred thirty-nine".