216432661 has 8 divisors (see below), whose sum is σ = 229495680. Its totient is φ = 203406528.

The previous prime is 216432641. The next prime is 216432677. The reversal of 216432661 is 166234612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 216432661 - 2¹³ = 216424469 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 (216432641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3370 + ... + 21076.

It is an arithmetic number, because the mean of its divisors is an integer number (28686960).

Almost surely, 2^216432661 is an apocalyptic number.

It is an amenable number.

216432661 is a deficient number, since it is larger than the sum of its proper divisors (13063019).

216432661 is a wasteful number, since it uses less digits than its factorization.

216432661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18443.

The product of its digits is 10368, while the sum is 31.

The square root of 216432661 is about 14711.6505192313. The cubic root of 216432661 is about 600.4003448510.

The spelling of 216432661 in words is "two hundred sixteen million, four hundred thirty-two thousand, six hundred sixty-one".