20479843854 has 24 divisors (see below), whose sum is σ = 44524450152. Its totient is φ = 6803313840.

The previous prime is 20479843847. The next prime is 20479843859. The reversal of 20479843854 is 45834897402.

It is a self number, because there is not a number n which added to its sum of digits gives 20479843854.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20479843859) 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, 1936312 + ... + 1946859.

It is an arithmetic number, because the mean of its divisors is an integer number (1855185423).

Almost surely, 2^20479843854 is an apocalyptic number.

20479843854 is an abundant number, since it is smaller than the sum of its proper divisors (24044606298).

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

20479843854 is a wasteful number, since it uses less digits than its factorization.

20479843854 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3883472 (or 3883469 counting only the distinct ones).

The product of its (nonzero) digits is 7741440, while the sum is 54.

The spelling of 20479843854 in words is "twenty billion, four hundred seventy-nine million, eight hundred forty-three thousand, eight hundred fifty-four".