20887979886 has 24 divisors (see below), whose sum is σ = 45266200824. Its totient is φ = 6961289040.

The previous prime is 20887979881. The next prime is 20887979891. The reversal of 20887979886 is 68897978802.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (20887979881) and next prime (20887979891).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20887979881) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18100 + ... + 205191.

It is an arithmetic number, because the mean of its divisors is an integer number (1886091701).

Almost surely, 2^20887979886 is an apocalyptic number.

20887979886 is an abundant number, since it is smaller than the sum of its proper divisors (24378220938).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20887979886 is a wasteful number, since it uses less digits than its factorization.

20887979886 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 228496 (or 228493 counting only the distinct ones).

The product of its (nonzero) digits is 195084288, while the sum is 72.

The spelling of 20887979886 in words is "twenty billion, eight hundred eighty-seven million, nine hundred seventy-nine thousand, eight hundred eighty-six".