216493491 has 8 divisors (see below), whose sum is σ = 297969664. Its totient is φ = 139673160.

The previous prime is 216493483. The next prime is 216493507. The reversal of 216493491 is 194394612.

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

It is not a de Polignac number, because 216493491 - 2³ = 216493483 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216493451) 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, 1163851 + ... + 1164036.

It is an arithmetic number, because the mean of its divisors is an integer number (37246208).

Almost surely, 2^216493491 is an apocalyptic number.

216493491 is a deficient number, since it is larger than the sum of its proper divisors (81476173).

216493491 is a wasteful number, since it uses less digits than its factorization.

216493491 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2327921.

The product of its digits is 46656, while the sum is 39.

The square root of 216493491 is about 14713.7177830758. The cubic root of 216493491 is about 600.4565885678.

The spelling of 216493491 in words is "two hundred sixteen million, four hundred ninety-three thousand, four hundred ninety-one".