20684361572 has 54 divisors (see below), whose sum is σ = 42351097698. Its totient is φ = 8813564928.

The previous prime is 20684361527. The next prime is 20684361589. The reversal of 20684361572 is 27516348602.

It can be written as a sum of positive squares in 3 ways, for example, as 67996516 + 20616365056 = 8246^2 + 143584^2 .

It is a super-2 number, since 2×20684361572² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 30734228 + ... + 30734900.

It is an arithmetic number, because the mean of its divisors is an integer number (784279587).

Almost surely, 2^20684361572 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20684361572, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21175548849).

20684361572 is an abundant number, since it is smaller than the sum of its proper divisors (21666736126).

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

20684361572 is an equidigital number, since it uses as much as digits as its factorization.

20684361572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1597 (or 915 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 44.

The spelling of 20684361572 in words is "twenty billion, six hundred eighty-four million, three hundred sixty-one thousand, five hundred seventy-two".