216492187 has 4 divisors (see below), whose sum is σ = 218635776. Its totient is φ = 214348600.

The previous prime is 216492151. The next prime is 216492223. The reversal of 216492187 is 781294612.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (216492151) and next prime (216492223).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-216492187 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216493187) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1071643 + ... + 1071844.

It is an arithmetic number, because the mean of its divisors is an integer number (54658944).

Almost surely, 2^216492187 is an apocalyptic number.

216492187 is a deficient number, since it is larger than the sum of its proper divisors (2143589).

216492187 is a wasteful number, since it uses less digits than its factorization.

216492187 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2143588.

The product of its digits is 48384, while the sum is 40.

The square root of 216492187 is about 14713.6734706191. The cubic root of 216492187 is about 600.4553829935.

The spelling of 216492187 in words is "two hundred sixteen million, four hundred ninety-two thousand, one hundred eighty-seven".