21738891305 has 8 divisors (see below), whose sum is σ = 26088000000. Its totient is φ = 17390226096.

The previous prime is 21738891283. The next prime is 21738891337. The reversal of 21738891305 is 50319883712.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21738891305 - 2⁶ = 21738891241 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21738891305.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8696 + ... + 208694.

It is an arithmetic number, because the mean of its divisors is an integer number (3261000000).

Almost surely, 2^21738891305 is an apocalyptic number.

It is an amenable number.

21738891305 is a deficient number, since it is larger than the sum of its proper divisors (4349108695).

21738891305 is a wasteful number, since it uses less digits than its factorization.

21738891305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221743.

The product of its (nonzero) digits is 362880, while the sum is 47.

The spelling of 21738891305 in words is "twenty-one billion, seven hundred thirty-eight million, eight hundred ninety-one thousand, three hundred five".