21543423234460 has 48 divisors (see below), whose sum is σ = 45891062687232. Its totient is φ = 8493650849600.

The previous prime is 21543423234451. The next prime is 21543423234479. The reversal of 21543423234460 is 6443232434512.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3050895 + ... + 7238425.

It is an arithmetic number, because the mean of its divisors is an integer number (956063805984).

Almost surely, 2^{21543423234460} is an apocalyptic number.

21543423234460 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21543423234460 is an abundant number, since it is smaller than the sum of its proper divisors (24347639452772).

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

21543423234460 is a wasteful number, since it uses less digits than its factorization.

21543423234460 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4191234 (or 4191232 counting only the distinct ones).

The product of its (nonzero) digits is 1658880, while the sum is 43.

Adding to 21543423234460 its reverse (6443232434512), we get a palindrome (27986655668972).

The spelling of 21543423234460 in words is "twenty-one trillion, five hundred forty-three billion, four hundred twenty-three million, two hundred thirty-four thousand, four hundred sixty".