20431907 has 4 divisors (see below), whose sum is σ = 20448696. Its totient is φ = 20415120.

The previous prime is 20431891. The next prime is 20431913. The reversal of 20431907 is 70913402.

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 20431907 - 2⁴ = 20431891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20431967) 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, 6413 + ... + 9054.

It is an arithmetic number, because the mean of its divisors is an integer number (5112174).

Almost surely, 2^20431907 is an apocalyptic number.

20431907 is a deficient number, since it is larger than the sum of its proper divisors (16789).

20431907 is a wasteful number, since it uses less digits than its factorization.

20431907 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16788.

The product of its (nonzero) digits is 1512, while the sum is 26.

The square root of 20431907 is about 4520.1667004658. The cubic root of 20431907 is about 273.3818224835.

The spelling of 20431907 in words is "twenty million, four hundred thirty-one thousand, nine hundred seven".