20445779754 has 80 divisors (see below), whose sum is σ = 47326276008. Its totient is φ = 6592399488.

The previous prime is 20445779747. The next prime is 20445779801. The reversal of 20445779754 is 45797754402.

20445779754 is a `hidden beast` number, since 20 + 44 + 577 + 9 + 7 + 5 + 4 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 19704579129 + 741200625 = 140373^2 + 27225^2 .

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 20445779754.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 1027104 + ... + 1046820.

Almost surely, 2^20445779754 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20445779754, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23663138004).

20445779754 is an abundant number, since it is smaller than the sum of its proper divisors (26880496254).

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

20445779754 is a wasteful number, since it uses less digits than its factorization.

20445779754 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19941 (or 19932 counting only the distinct ones).

The product of its (nonzero) digits is 9878400, while the sum is 54.

The spelling of 20445779754 in words is "twenty billion, four hundred forty-five million, seven hundred seventy-nine thousand, seven hundred fifty-four".