216642575 has 6 divisors (see below), whose sum is σ = 268636824. Its totient is φ = 173314040.

The previous prime is 216642571. The next prime is 216642593. The reversal of 216642575 is 575246612.

It is not a de Polignac number, because 216642575 - 2² = 216642571 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216642571) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4332827 + ... + 4332876.

It is an arithmetic number, because the mean of its divisors is an integer number (44772804).

Almost surely, 2^216642575 is an apocalyptic number.

216642575 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

216642575 is a deficient number, since it is larger than the sum of its proper divisors (51994249).

216642575 is an equidigital number, since it uses as much as digits as its factorization.

216642575 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8665713 (or 8665708 counting only the distinct ones).

The product of its digits is 100800, while the sum is 38.

The square root of 216642575 is about 14718.7830679034. The cubic root of 216642575 is about 600.5943878293.

The spelling of 216642575 in words is "two hundred sixteen million, six hundred forty-two thousand, five hundred seventy-five".