20428513816866 has 16 divisors (see below), whose sum is σ = 41627914948224. Its totient is φ = 6681023386544.

The previous prime is 20428513816787. The next prime is 20428513816871. The reversal of 20428513816866 is 66861831582402.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 32120304426 + ... + 32120305061.

It is an arithmetic number, because the mean of its divisors is an integer number (2601744684264).

Almost surely, 2^{20428513816866} is an apocalyptic number.

20428513816866 is an abundant number, since it is smaller than the sum of its proper divisors (21199401131358).

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

20428513816866 is a wasteful number, since it uses less digits than its factorization.

20428513816866 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64240609545.

The product of its (nonzero) digits is 26542080, while the sum is 60.

The spelling of 20428513816866 in words is "twenty trillion, four hundred twenty-eight billion, five hundred thirteen million, eight hundred sixteen thousand, eight hundred sixty-six".