213717691 has 8 divisors (see below), whose sum is σ = 235211184. Its totient is φ = 192568320.

The previous prime is 213717683. The next prime is 213717701. The reversal of 213717691 is 196717312.

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 213717691 - 2³ = 213717683 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 213717691.

It is not an unprimeable number, because it can be changed into a prime (213717991) 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, 84726 + ... + 87211.

It is an arithmetic number, because the mean of its divisors is an integer number (29401398).

Almost surely, 2^213717691 is an apocalyptic number.

213717691 is a deficient number, since it is larger than the sum of its proper divisors (21493493).

213717691 is a wasteful number, since it uses less digits than its factorization.

213717691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172061.

The product of its digits is 15876, while the sum is 37.

The square root of 213717691 is about 14619.0865309704. The cubic root of 213717691 is about 597.8792638880.

The spelling of 213717691 in words is "two hundred thirteen million, seven hundred seventeen thousand, six hundred ninety-one".