21442055 has 8 divisors (see below), whose sum is σ = 26426112. Its totient is φ = 16689888.

The previous prime is 21442037. The next prime is 21442063. The reversal of 21442055 is 55024412.

It is a happy number.

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 21442055 - 2¹⁰ = 21441031 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21442055.

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, 57767 + ... + 58136.

It is an arithmetic number, because the mean of its divisors is an integer number (3303264).

Almost surely, 2^21442055 is an apocalyptic number.

21442055 is a deficient number, since it is larger than the sum of its proper divisors (4984057).

21442055 is a wasteful number, since it uses less digits than its factorization.

21442055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115945.

The product of its (nonzero) digits is 1600, while the sum is 23.

The square root of 21442055 is about 4630.5566620008. The cubic root of 21442055 is about 277.8148578352.

Adding to 21442055 its reverse (55024412), we get a palindrome (76466467).

The spelling of 21442055 in words is "twenty-one million, four hundred forty-two thousand, fifty-five".