21867554 has 8 divisors (see below), whose sum is σ = 32885148. Its totient is φ = 10905840.

The previous prime is 21867553. The next prime is 21867581. The reversal of 21867554 is 45576812.

It can be written as a sum of positive squares in 2 ways, for example, as 21836929 + 30625 = 4673^2 + 175^2 .

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 (21867551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12977 + ... + 14564.

Almost surely, 2^21867554 is an apocalyptic number.

21867554 is a deficient number, since it is larger than the sum of its proper divisors (11017594).

21867554 is a wasteful number, since it uses less digits than its factorization.

21867554 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27940.

The product of its digits is 67200, while the sum is 38.

The square root of 21867554 is about 4676.2756548347. The cubic root of 21867554 is about 279.6404995083.

The spelling of 21867554 in words is "twenty-one million, eight hundred sixty-seven thousand, five hundred fifty-four".