20781832704 has 80 divisors (see below), whose sum is σ = 55696310208. Its totient is φ = 6885711872.

The previous prime is 20781832693. The next prime is 20781832723. The reversal of 20781832704 is 40723818702.

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, 216004 + ... + 297020.

Almost surely, 2^20781832704 is an apocalyptic number.

20781832704 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20781832704, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27848155104).

20781832704 is an abundant number, since it is smaller than the sum of its proper divisors (34914477504).

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

20781832704 is an equidigital number, since it uses as much as digits as its factorization.

20781832704 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81205 (or 81189 counting only the distinct ones).

The product of its (nonzero) digits is 150528, while the sum is 42.

The spelling of 20781832704 in words is "twenty billion, seven hundred eighty-one million, eight hundred thirty-two thousand, seven hundred four".