20464399872 has 400 divisors, whose sum is σ = 70407770400. Its totient is φ = 5796790272.

The previous prime is 20464399871. The next prime is 20464399897. The reversal of 20464399872 is 27899346402.

20464399872 is a `hidden beast` number, since 20 + 464 + 3 + 9 + 98 + 72 = 666.

It is a super-2 number, since 2×20464399872² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20464399871) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 45577504 + ... + 45577952.

It is an arithmetic number, because the mean of its divisors is an integer number (176019426).

Almost surely, 2^20464399872 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 20464399872, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35203885200).

20464399872 is an abundant number, since it is smaller than the sum of its proper divisors (49943370528).

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

20464399872 is an equidigital number, since it uses as much as digits as its factorization.

20464399872 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 643 (or 618 counting only the distinct ones).

The product of its (nonzero) digits is 5225472, while the sum is 54.

The spelling of 20464399872 in words is "twenty billion, four hundred sixty-four million, three hundred ninety-nine thousand, eight hundred seventy-two".