216239979 has 16 divisors (see below), whose sum is σ = 300625920. Its totient is φ = 138085920.

The previous prime is 216239963. The next prime is 216239981. The reversal of 216239979 is 979932612.

It is not a de Polignac number, because 216239979 - 2⁴ = 216239963 is a prime.

It is a super-3 number, since 3×216239979³ (a number of 26 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (216239909) 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 in 15 ways as a sum of consecutive naturals, for example, 1264 + ... + 20834.

It is an arithmetic number, because the mean of its divisors is an integer number (18789120).

Almost surely, 2^216239979 is an apocalyptic number.

216239979 is a gapful number since it is divisible by the number (29) formed by its first and last digit.

216239979 is a deficient number, since it is larger than the sum of its proper divisors (84385941).

216239979 is a wasteful number, since it uses less digits than its factorization.

216239979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19730.

The product of its digits is 367416, while the sum is 48.

The square root of 216239979 is about 14705.1004416835. The cubic root of 216239979 is about 600.2221205384. Note that the first 3 decimals are identical.

The spelling of 216239979 in words is "two hundred sixteen million, two hundred thirty-nine thousand, nine hundred seventy-nine".