20907907 has 4 divisors (see below), whose sum is σ = 21103416. Its totient is φ = 20712400.

The previous prime is 20907893. The next prime is 20907911. The reversal of 20907907 is 70970902.

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

It is a cyclic number.

It is not a de Polignac number, because 20907907 - 2¹⁵ = 20875139 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20907937) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 97594 + ... + 97807.

It is an arithmetic number, because the mean of its divisors is an integer number (5275854).

Almost surely, 2^20907907 is an apocalyptic number.

20907907 is a deficient number, since it is larger than the sum of its proper divisors (195509).

20907907 is a wasteful number, since it uses less digits than its factorization.

20907907 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195508.

The product of its (nonzero) digits is 7938, while the sum is 34.

The square root of 20907907 is about 4572.5164843880. The cubic root of 20907907 is about 275.4885288750.

The spelling of 20907907 in words is "twenty million, nine hundred seven thousand, nine hundred seven".