21644486371 has 8 divisors (see below), whose sum is σ = 22491262080. Its totient is φ = 20804404992.

The previous prime is 21644486267. The next prime is 21644486393. The reversal of 21644486371 is 17368444612.

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 21644486371 - 2⁹ = 21644485859 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21644496371) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1666990 + ... + 1679923.

It is an arithmetic number, because the mean of its divisors is an integer number (2811407760).

Almost surely, 2^21644486371 is an apocalyptic number.

21644486371 is a deficient number, since it is larger than the sum of its proper divisors (846775709).

21644486371 is a wasteful number, since it uses less digits than its factorization.

21644486371 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3347165.

The product of its digits is 774144, while the sum is 46.

The spelling of 21644486371 in words is "twenty-one billion, six hundred forty-four million, four hundred eighty-six thousand, three hundred seventy-one".