20406778404 has 12 divisors (see below), whose sum is σ = 47615816304. Its totient is φ = 6802259464.

The previous prime is 20406778397. The next prime is 20406778417. The reversal of 20406778404 is 40487760402.

It is a tau number, because it is divible by the number of its divisors (12).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 850282422 + ... + 850282445.

It is an arithmetic number, because the mean of its divisors is an integer number (3967984692).

Almost surely, 2^20406778404 is an apocalyptic number.

It is an amenable number.

20406778404 is an abundant number, since it is smaller than the sum of its proper divisors (27209037900).

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

20406778404 is a wasteful number, since it uses less digits than its factorization.

20406778404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1700564874 (or 1700564872 counting only the distinct ones).

The product of its (nonzero) digits is 301056, while the sum is 42.

The spelling of 20406778404 in words is "twenty billion, four hundred six million, seven hundred seventy-eight thousand, four hundred four".