21612055 has 8 divisors (see below), whose sum is σ = 25974000. Its totient is φ = 17263296.

The previous prime is 21612037. The next prime is 21612061. The reversal of 21612055 is 55021612.

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 21612055 - 2⁵ = 21612023 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 771 + ... + 6619.

It is an arithmetic number, because the mean of its divisors is an integer number (3246750).

Almost surely, 2^21612055 is an apocalyptic number.

21612055 is a deficient number, since it is larger than the sum of its proper divisors (4361945).

21612055 is an equidigital number, since it uses as much as digits as its factorization.

21612055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6593.

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 21612055 is about 4648.8767460538. The cubic root of 21612055 is about 278.5471299679.

Adding to 21612055 its reverse (55021612), we get a palindrome (76633667).

The spelling of 21612055 in words is "twenty-one million, six hundred twelve thousand, fifty-five".