20986887 has 16 divisors (see below), whose sum is σ = 30015360. Its totient is φ = 13002912.

The previous prime is 20986883. The next prime is 20986897. The reversal of 20986887 is 78868902.

It is a happy number.

It is not a de Polignac number, because 20986887 - 2² = 20986883 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20986883) 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, 453 + ... + 6494.

It is an arithmetic number, because the mean of its divisors is an integer number (1875960).

Almost surely, 2^20986887 is an apocalyptic number.

20986887 is a deficient number, since it is larger than the sum of its proper divisors (9028473).

20986887 is a wasteful number, since it uses less digits than its factorization.

20986887 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7022.

The product of its (nonzero) digits is 387072, while the sum is 48.

The square root of 20986887 is about 4581.1447259391. The cubic root of 20986887 is about 275.8349806453.

The spelling of 20986887 in words is "twenty million, nine hundred eighty-six thousand, eight hundred eighty-seven".