21876555308644 has 9 divisors (see below), whose sum is σ = 38283988160467. Its totient is φ = 10938272977084.

The previous prime is 21876555308639. The next prime is 21876555308681. The reversal of 21876555308644 is 44680355567812.

The square root of 21876555308644 is 4677238.

It is a perfect power (a square), and thus also a powerful number.

It is a super-2 number, since 2×21876555308644² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 8185167 + ... + 10523785.

Almost surely, 2^{21876555308644} is an apocalyptic number.

21876555308644 is the 4677238-th square number.

It is an amenable number.

21876555308644 is a deficient number, since it is larger than the sum of its proper divisors (16407432851823).

21876555308644 is an frugal number, since it uses more digits than its factorization.

21876555308644 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4677242 (or 2338621 counting only the distinct ones).

The product of its (nonzero) digits is 193536000, while the sum is 64.

The spelling of 21876555308644 in words is "twenty-one trillion, eight hundred seventy-six billion, five hundred fifty-five million, three hundred eight thousand, six hundred forty-four".