20723721216 has 352 divisors, whose sum is σ = 63286296576. Its totient is φ = 5971968000.

The previous prime is 20723721209. The next prime is 20723721281. The reversal of 20723721216 is 61212732702.

It is a tau number, because it is divible by the number of its divisors (352).

It is a Harshad number since it is a multiple of its sum of digits (33).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 76471161 + ... + 76471431.

Almost surely, 2^20723721216 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 20723721216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31643148288).

20723721216 is an abundant number, since it is smaller than the sum of its proper divisors (42562575360).

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

20723721216 is a wasteful number, since it uses less digits than its factorization.

20723721216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 409 (or 391 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 33.

The spelling of 20723721216 in words is "twenty billion, seven hundred twenty-three million, seven hundred twenty-one thousand, two hundred sixteen".