21375132650556 has 12 divisors (see below), whose sum is σ = 49875309517992. Its totient is φ = 7125044216848.

The previous prime is 21375132650527. The next prime is 21375132650563. The reversal of 21375132650556 is 65505623157312.

It is a tau number, because it is divible by the number of its divisors (12).

It is a junction number, because it is equal to n+sod(n) for n = 21375132650499 and 21375132650508.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 890630527095 + ... + 890630527118.

It is an arithmetic number, because the mean of its divisors is an integer number (4156275793166).

Almost surely, 2^{21375132650556} is an apocalyptic number.

It is an amenable number.

21375132650556 is an abundant number, since it is smaller than the sum of its proper divisors (28500176867436).

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

21375132650556 is a wasteful number, since it uses less digits than its factorization.

21375132650556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1781261054220 (or 1781261054218 counting only the distinct ones).

The product of its (nonzero) digits is 5670000, while the sum is 51.

The spelling of 21375132650556 in words is "twenty-one trillion, three hundred seventy-five billion, one hundred thirty-two million, six hundred fifty thousand, five hundred fifty-six".