20487855 has 16 divisors (see below), whose sum is σ = 33120864. Its totient is φ = 10813440.

The previous prime is 20487853. The next prime is 20487877. The reversal of 20487855 is 55878402.

It is not a de Polignac number, because 20487855 - 2¹ = 20487853 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20487853) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5586 + ... + 8495.

It is an arithmetic number, because the mean of its divisors is an integer number (2070054).

Almost surely, 2^20487855 is an apocalyptic number.

20487855 is a deficient number, since it is larger than the sum of its proper divisors (12633009).

20487855 is a wasteful number, since it uses less digits than its factorization.

20487855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14186.

The product of its (nonzero) digits is 89600, while the sum is 39.

The square root of 20487855 is about 4526.3511794822. The cubic root of 20487855 is about 273.6311258021.

The spelling of 20487855 in words is "twenty million, four hundred eighty-seven thousand, eight hundred fifty-five".