20805207 has 8 divisors (see below), whose sum is σ = 27884784. Its totient is φ = 13797888.

The previous prime is 20805199. The next prime is 20805223. The reversal of 20805207 is 70250802.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20805207 - 2³ = 20805199 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20805287) 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, 17388 + ... + 18545.

It is an arithmetic number, because the mean of its divisors is an integer number (3485598).

Almost surely, 2^20805207 is an apocalyptic number.

20805207 is a deficient number, since it is larger than the sum of its proper divisors (7079577).

20805207 is a wasteful number, since it uses less digits than its factorization.

20805207 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36129.

The product of its (nonzero) digits is 1120, while the sum is 24.

The square root of 20805207 is about 4561.2725198129. The cubic root of 20805207 is about 275.0367201655.

It can be divided in two parts, 20805 and 207, that added together give a palindrome (21012).

The spelling of 20805207 in words is "twenty million, eight hundred five thousand, two hundred seven".