21667200018 has 8 divisors (see below), whose sum is σ = 43334400048. Its totient is φ = 7222400004.

The previous prime is 21667200011. The next prime is 21667200073. The reversal of 21667200018 is 81000276612.

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

21667200018 is an admirable number.

It is not an unprimeable number, because it can be changed into a prime (21667200011) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 1805599996 + ... + 1805600007.

It is an arithmetic number, because the mean of its divisors is an integer number (5416800006).

Almost surely, 2^21667200018 is an apocalyptic number.

21667200018 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21667200018 is a wasteful number, since it uses less digits than its factorization.

21667200018 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3611200008.

The product of its (nonzero) digits is 8064, while the sum is 33.

The spelling of 21667200018 in words is "twenty-one billion, six hundred sixty-seven million, two hundred thousand, eighteen".