21438717040556 has 6 divisors (see below), whose sum is σ = 37517754820980. Its totient is φ = 10719358520276.

The previous prime is 21438717040457. The next prime is 21438717040561. The reversal of 21438717040556 is 65504071783412.

It is a junction number, because it is equal to n+sod(n) for n = 21438717040498 and 21438717040507.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2679839630066 + ... + 2679839630073.

It is an arithmetic number, because the mean of its divisors is an integer number (6252959136830).

Almost surely, 2^{21438717040556} is an apocalyptic number.

It is an amenable number.

21438717040556 is a deficient number, since it is larger than the sum of its proper divisors (16079037780424).

21438717040556 is a wasteful number, since it uses less digits than its factorization.

21438717040556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5359679260143 (or 5359679260141 counting only the distinct ones).

The product of its (nonzero) digits is 5644800, while the sum is 53.

The spelling of 21438717040556 in words is "twenty-one trillion, four hundred thirty-eight billion, seven hundred seventeen million, forty thousand, five hundred fifty-six".