20673872640 has 432 divisors, whose sum is σ = 77914418400. Its totient is φ = 5041225728.

The previous prime is 20673872633. The next prime is 20673872647. The reversal of 20673872640 is 4627837602.

20673872640 is a `hidden beast` number, since 2 + 0 + 6 + 7 + 387 + 264 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (20673872633) and next prime (20673872647).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (20673872647) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6345892 + ... + 6349148.

It is an arithmetic number, because the mean of its divisors is an integer number (180357450).

Almost surely, 2^20673872640 is an apocalyptic number.

20673872640 is a gapful number since it is divisible by the number (20) 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 20673872640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38957209200).

20673872640 is an abundant number, since it is smaller than the sum of its proper divisors (57240545760).

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

20673872640 is a wasteful number, since it uses less digits than its factorization.

20673872640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3332 (or 3315 counting only the distinct ones).

The product of its (nonzero) digits is 677376, while the sum is 45.

It can be divided in two parts, 206738 and 72640, that added together give a triangular number (279378 = T₇₄₇).

The spelling of 20673872640 in words is "twenty billion, six hundred seventy-three million, eight hundred seventy-two thousand, six hundred forty".