21543614540 has 48 divisors (see below), whose sum is σ = 53487604800. Its totient is φ = 7131677952.

The previous prime is 21543614527. The next prime is 21543614581. The reversal of 21543614540 is 4541634512.

It is a super-3 number, since 3×21543614540³ (a number of 32 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a self number, because there is not a number n which added to its sum of digits gives 21543614540.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2649095 + ... + 2657214.

It is an arithmetic number, because the mean of its divisors is an integer number (1114325100).

Almost surely, 2^21543614540 is an apocalyptic number.

21543614540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21543614540 is an abundant number, since it is smaller than the sum of its proper divisors (31943990260).

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

21543614540 is a wasteful number, since it uses less digits than its factorization.

21543614540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5306354 (or 5306352 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 35.

The spelling of 21543614540 in words is "twenty-one billion, five hundred forty-three million, six hundred fourteen thousand, five hundred forty".