20307705 has 16 divisors (see below), whose sum is σ = 35446464. Its totient is φ = 9846080.

The previous prime is 20307691. The next prime is 20307719. The reversal of 20307705 is 50770302.

It is an interprime number because it is at equal distance from previous prime (20307691) and next prime (20307719).

It is not a de Polignac number, because 20307705 - 2⁶ = 20307641 is a prime.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 61374 + ... + 61703.

It is an arithmetic number, because the mean of its divisors is an integer number (2215404).

Almost surely, 2^20307705 is an apocalyptic number.

It is an amenable number.

20307705 is a deficient number, since it is larger than the sum of its proper divisors (15138759).

20307705 is a wasteful number, since it uses less digits than its factorization.

20307705 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 123096.

The product of its (nonzero) digits is 1470, while the sum is 24.

The square root of 20307705 is about 4506.4071054444. The cubic root of 20307705 is about 272.8267494187.

It can be divided in two parts, 20307 and 705, that added together give a palindrome (21012).

The spelling of 20307705 in words is "twenty million, three hundred seven thousand, seven hundred five".