21637343378986 has 8 divisors (see below), whose sum is σ = 32570700634944. Its totient is φ = 10780443167340.

The previous prime is 21637343378983. The next prime is 21637343379013. The reversal of 21637343378986 is 68987334373612.

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

It is not an unprimeable number, because it can be changed into a prime (21637343378983) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19114260370 + ... + 19114261501.

It is an arithmetic number, because the mean of its divisors is an integer number (4071337579368).

Almost surely, 2^{21637343378986} is an apocalyptic number.

21637343378986 is a deficient number, since it is larger than the sum of its proper divisors (10933357255958).

21637343378986 is a wasteful number, since it uses less digits than its factorization.

21637343378986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38228522156.

The product of its digits is 658409472, while the sum is 70.

The spelling of 21637343378986 in words is "twenty-one trillion, six hundred thirty-seven billion, three hundred forty-three million, three hundred seventy-eight thousand, nine hundred eighty-six".