216500639 has 2 divisors, whose sum is σ = 216500640. Its totient is φ = 216500638.

The previous prime is 216500617. The next prime is 216500681. The reversal of 216500639 is 936005612.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-216500639 is a prime.

It is a Chen prime.

It is equal to p_11940494 and since 216500639 and 11940494 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (216500239) 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, 108250319 + 108250320.

It is an arithmetic number, because the mean of its divisors is an integer number (108250320).

Almost surely, 2^216500639 is an apocalyptic number.

216500639 is a deficient number, since it is larger than the sum of its proper divisors (1).

216500639 is an equidigital number, since it uses as much as digits as its factorization.

216500639 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 9720, while the sum is 32.

The square root of 216500639 is about 14713.9606836501. The cubic root of 216500639 is about 600.4631969519.

The spelling of 216500639 in words is "two hundred sixteen million, five hundred thousand, six hundred thirty-nine".