216642590 has 16 divisors (see below), whose sum is σ = 390126240. Its totient is φ = 86619360.

The previous prime is 216642571. The next prime is 216642593. The reversal of 216642590 is 95246612.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 216642590.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216642593) 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, 37175 + ... + 42605.

It is an arithmetic number, because the mean of its divisors is an integer number (24382890).

Almost surely, 2^216642590 is an apocalyptic number.

216642590 is a deficient number, since it is larger than the sum of its proper divisors (173483650).

216642590 is a wasteful number, since it uses less digits than its factorization.

216642590 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9427.

The product of its (nonzero) digits is 25920, while the sum is 35.

The square root of 216642590 is about 14718.7835774564. The cubic root of 216642590 is about 600.5944016907.

The spelling of 216642590 in words is "two hundred sixteen million, six hundred forty-two thousand, five hundred ninety".