213987 has 4 divisors (see below), whose sum is σ = 285320. Its totient is φ = 142656.

The previous prime is 213977. The next prime is 213989. The reversal of 213987 is 789312.

It is a happy number.

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

It is not a de Polignac number, because 213987 - 2⁷ = 213859 is a prime.

It is a D-number.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 213987.

It is not an unprimeable number, because it can be changed into a prime (213989) 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, 35662 + ... + 35667.

It is an arithmetic number, because the mean of its divisors is an integer number (71330).

2²¹³⁹⁸⁷ is an apocalyptic number.

213987 is a deficient number, since it is larger than the sum of its proper divisors (71333).

213987 is an equidigital number, since it uses as much as digits as its factorization.

213987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 71332.

The product of its digits is 3024, while the sum is 30.

The square root of 213987 is about 462.5872890601. The cubic root of 213987 is about 59.8130290809.

The spelling of 213987 in words is "two hundred thirteen thousand, nine hundred eighty-seven".