213639 has 16 divisors (see below), whose sum is σ = 311040. Its totient is φ = 129920.

The previous prime is 213637. The next prime is 213641. The reversal of 213639 is 936312.

It is an interprime number because it is at equal distance from previous prime (213637) and next prime (213641).

It is a cyclic number.

It is not a de Polignac number, because 213639 - 2¹ = 213637 is a prime.

213639 is a modest number, since divided by 639 gives 213 as remainder.

It is a plaindrome in base 14.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 213639.

It is not an unprimeable number, because it can be changed into a prime (213637) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2974 + ... + 3044.

It is an arithmetic number, because the mean of its divisors is an integer number (19440).

2²¹³⁶³⁹ is an apocalyptic number.

213639 is a deficient number, since it is larger than the sum of its proper divisors (97401).

213639 is a wasteful number, since it uses less digits than its factorization.

213639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 150.

The product of its digits is 972, while the sum is 24.

The square root of 213639 is about 462.2109907823. The cubic root of 213639 is about 59.7805875029.

The spelling of 213639 in words is "two hundred thirteen thousand, six hundred thirty-nine".