20884691 has 4 divisors (see below), whose sum is σ = 21037272. Its totient is φ = 20732112.

The previous prime is 20884673. The next prime is 20884693. The reversal of 20884691 is 19648802.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20884691 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20884693) 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, 76085 + ... + 76358.

It is an arithmetic number, because the mean of its divisors is an integer number (5259318).

Almost surely, 2^20884691 is an apocalyptic number.

20884691 is a deficient number, since it is larger than the sum of its proper divisors (152581).

20884691 is a wasteful number, since it uses less digits than its factorization.

20884691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152580.

The product of its (nonzero) digits is 27648, while the sum is 38.

The square root of 20884691 is about 4569.9771334220. The cubic root of 20884691 is about 275.3865242377.

The spelling of 20884691 in words is "twenty million, eight hundred eighty-four thousand, six hundred ninety-one".