20457887 has 4 divisors (see below), whose sum is σ = 20571096. Its totient is φ = 20344680.

The previous prime is 20457863. The next prime is 20457901. The reversal of 20457887 is 78875402.

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 20457887 - 2⁶ = 20457823 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20457187) 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, 56333 + ... + 56694.

It is an arithmetic number, because the mean of its divisors is an integer number (5142774).

Almost surely, 2^20457887 is an apocalyptic number.

20457887 is a deficient number, since it is larger than the sum of its proper divisors (113209).

20457887 is a wasteful number, since it uses less digits than its factorization.

20457887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113208.

The product of its (nonzero) digits is 125440, while the sum is 41.

The square root of 20457887 is about 4523.0395753298. The cubic root of 20457887 is about 273.4976454383.

The spelling of 20457887 in words is "twenty million, four hundred fifty-seven thousand, eight hundred eighty-seven".