216186490 has 24 divisors (see below), whose sum is σ = 421375068. Its totient is φ = 79822080.

The previous prime is 216186469. The next prime is 216186491. The reversal of 216186490 is 94681612.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 32936121 + 183250369 = 5739^2 + 13537^2 .

It is a Smith number, since the sum of its digits (37) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216186491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 62271 + ... + 65650.

Almost surely, 2^216186490 is an apocalyptic number.

216186490 is a deficient number, since it is larger than the sum of its proper divisors (205188578).

216186490 is a wasteful number, since it uses less digits than its factorization.

216186490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 127954 (or 127941 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 216186490 is about 14703.2816064986. The cubic root of 216186490 is about 600.1726262548.

The spelling of 216186490 in words is "two hundred sixteen million, one hundred eighty-six thousand, four hundred ninety".