2543664420 has 108 divisors (see below), whose sum is σ = 8481056220. Its totient is φ = 616640640.

The previous prime is 2543664407. The next prime is 2543664427. The reversal of 2543664420 is 244663452.

2543664420 is a `hidden beast` number, since 2 + 5 + 4 + 3 + 6 + 644 + 2 + 0 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 310534884 + 2233129536 = 17622^2 + 47256^2 .

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

It is not an unprimeable number, because it can be changed into a prime (2543664427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 36615 + ... + 80174.

Almost surely, 2^2543664420 is an apocalyptic number.

2543664420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2543664420 is an abundant number, since it is smaller than the sum of its proper divisors (5937391800).

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

2543664420 is a wasteful number, since it uses less digits than its factorization.

2543664420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 116826 (or 116810 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 36.

The square root of 2543664420 is about 50434.7540888225. The cubic root of 2543664420 is about 1365.0648119610.

The spelling of 2543664420 in words is "two billion, five hundred forty-three million, six hundred sixty-four thousand, four hundred twenty".