20438334720 has 360 divisors, whose sum is σ = 75503070720. Its totient is φ = 5273579520.

The previous prime is 20438334691. The next prime is 20438334731. The reversal of 20438334720 is 2743383402.

20438334720 is a `hidden beast` number, since 204 + 383 + 3 + 4 + 72 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (360).

It is a super-2 number, since 2×20438334720² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 3210901 + ... + 3217259.

It is an arithmetic number, because the mean of its divisors is an integer number (209730752).

Almost surely, 2^20438334720 is an apocalyptic number.

20438334720 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 20438334720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37751535360).

20438334720 is an abundant number, since it is smaller than the sum of its proper divisors (55064736000).

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

20438334720 is an equidigital number, since it uses as much as digits as its factorization.

20438334720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6423 (or 6400 counting only the distinct ones).

The product of its (nonzero) digits is 96768, while the sum is 36.

The spelling of 20438334720 in words is "twenty billion, four hundred thirty-eight million, three hundred thirty-four thousand, seven hundred twenty".