187856213 has 2 divisors, whose sum is σ = 187856214. Its totient is φ = 187856212.

The previous prime is 187856209. The next prime is 187856243. The reversal of 187856213 is 312658781.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 176411524 + 11444689 = 13282^2 + 3383^2 .

It is a cyclic number.

It is not a de Polignac number, because 187856213 - 2² = 187856209 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (187856243) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 93928106 + 93928107.

It is an arithmetic number, because the mean of its divisors is an integer number (93928107).

Almost surely, 2^187856213 is an apocalyptic number.

It is an amenable number.

187856213 is a deficient number, since it is larger than the sum of its proper divisors (1).

187856213 is an equidigital number, since it uses as much as digits as its factorization.

187856213 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 80640, while the sum is 41.

The square root of 187856213 is about 13706.0648254705. The cubic root of 187856213 is about 572.7193471826.

The spelling of 187856213 in words is "one hundred eighty-seven million, eight hundred fifty-six thousand, two hundred thirteen".