21801306606878 has 8 divisors (see below), whose sum is σ = 32740297497768. Its totient is φ = 10887874107624.

The previous prime is 21801306606869. The next prime is 21801306606917. The reversal of 21801306606878 is 87860660310812.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6389595776 + ... + 6389599187.

It is an arithmetic number, because the mean of its divisors is an integer number (4092537187221).

Almost surely, 2^{21801306606878} is an apocalyptic number.

21801306606878 is a deficient number, since it is larger than the sum of its proper divisors (10938990890890).

21801306606878 is a wasteful number, since it uses less digits than its factorization.

21801306606878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12779195818.

The product of its (nonzero) digits is 4644864, while the sum is 56.

The spelling of 21801306606878 in words is "twenty-one trillion, eight hundred one billion, three hundred six million, six hundred six thousand, eight hundred seventy-eight".