20847749760 has 128 divisors (see below), whose sum is σ = 73835841600. Its totient is φ = 5559395328.

The previous prime is 20847749687. The next prime is 20847749803. The reversal of 20847749760 is 6794774802.

20847749760 is a `hidden beast` number, since 2 + 0 + 84 + 77 + 497 + 6 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Smith number, since the sum of its digits (54) coincides with the sum of the digits of its prime factors.

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

It is a junction number, because it is equal to n+sod(n) for n = 20847749697 and 20847749706.

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 15 ways as a sum of consecutive naturals, for example, 585954 + ... + 620513.

Almost surely, 2^20847749760 is an apocalyptic number.

20847749760 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20847749760 is an abundant number, since it is smaller than the sum of its proper divisors (52988091840).

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

20847749760 is a wasteful number, since it uses less digits than its factorization.

20847749760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1206495 (or 1206477 counting only the distinct ones).

The product of its (nonzero) digits is 4741632, while the sum is 54.

The spelling of 20847749760 in words is "twenty billion, eight hundred forty-seven million, seven hundred forty-nine thousand, seven hundred sixty".