187666213 has 8 divisors (see below), whose sum is σ = 227092032. Its totient is φ = 151394496.

The previous prime is 187666169. The next prime is 187666229. The reversal of 187666213 is 312666781.

It is a happy number.

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 187666213 - 2⁹ = 187665701 is a prime.

It is a super-2 number, since 2×187666213² = 70437215003522738, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (187666243) 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, 788395 + ... + 788632.

It is an arithmetic number, because the mean of its divisors is an integer number (28386504).

Almost surely, 2^187666213 is an apocalyptic number.

It is an amenable number.

187666213 is a deficient number, since it is larger than the sum of its proper divisors (39425819).

187666213 is a wasteful number, since it uses less digits than its factorization.

187666213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1577051.

The product of its digits is 72576, while the sum is 40.

The square root of 187666213 is about 13699.1318338061. The cubic root of 187666213 is about 572.5261970049.

The spelling of 187666213 in words is "one hundred eighty-seven million, six hundred sixty-six thousand, two hundred thirteen".