213705 has 16 divisors (see below), whose sum is σ = 380160. Its totient is φ = 113904.

The previous prime is 213659. The next prime is 213713. The reversal of 213705 is 507312.

It is not a de Polignac number, because 213705 - 2⁶ = 213641 is a prime.

It is an Ulam number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 657 + ... + 926.

It is an arithmetic number, because the mean of its divisors is an integer number (23760).

2²¹³⁷⁰⁵ is an apocalyptic number.

It is an amenable number.

213705 is a deficient number, since it is larger than the sum of its proper divisors (166455).

213705 is a wasteful number, since it uses less digits than its factorization.

213705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1597 (or 1591 counting only the distinct ones).

The product of its (nonzero) digits is 210, while the sum is 18.

The square root of 213705 is about 462.2823812347. The cubic root of 213705 is about 59.7867429217.

The spelling of 213705 in words is "two hundred thirteen thousand, seven hundred five".