216526639 has 8 divisors (see below), whose sum is σ = 252509600. Its totient is φ = 185593968.

The previous prime is 216526633. The next prime is 216526649. The reversal of 216526639 is 936625612.

It is not a de Polignac number, because 216526639 - 2³ = 216526631 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216526631) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 315294 + ... + 315979.

It is an arithmetic number, because the mean of its divisors is an integer number (31563700).

Almost surely, 2^216526639 is an apocalyptic number.

216526639 is a deficient number, since it is larger than the sum of its proper divisors (35982961).

216526639 is an frugal number, since it uses more digits than its factorization.

216526639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 631294 (or 631280 counting only the distinct ones).

The product of its digits is 116640, while the sum is 40.

The square root of 216526639 is about 14714.8441717879. The cubic root of 216526639 is about 600.4872329367.

The spelling of 216526639 in words is "two hundred sixteen million, five hundred twenty-six thousand, six hundred thirty-nine".