21735055 has 4 divisors (see below), whose sum is σ = 26082072. Its totient is φ = 17388040.

The previous prime is 21735053. The next prime is 21735073. The reversal of 21735055 is 55053712.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 21735055 - 2¹ = 21735053 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21735053) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2173501 + ... + 2173510.

It is an arithmetic number, because the mean of its divisors is an integer number (6520518).

Almost surely, 2^21735055 is an apocalyptic number.

21735055 is a deficient number, since it is larger than the sum of its proper divisors (4347017).

21735055 is an equidigital number, since it uses as much as digits as its factorization.

21735055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4347016.

The product of its (nonzero) digits is 5250, while the sum is 28.

The square root of 21735055 is about 4662.0869790256. The cubic root of 21735055 is about 279.0745594507.

Adding to 21735055 its reverse (55053712), we get a palindrome (76788767).

The spelling of 21735055 in words is "twenty-one million, seven hundred thirty-five thousand, fifty-five".