21024055 has 16 divisors (see below), whose sum is σ = 27334944. Its totient is φ = 15431040.

The previous prime is 21023971. The next prime is 21024067. The reversal of 21024055 is 55042012.

It is not a de Polignac number, because 21024055 - 2¹¹ = 21022007 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10872 + ... + 12658.

It is an arithmetic number, because the mean of its divisors is an integer number (1708434).

Almost surely, 2^21024055 is an apocalyptic number.

21024055 is a deficient number, since it is larger than the sum of its proper divisors (6310889).

21024055 is a wasteful number, since it uses less digits than its factorization.

21024055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1986.

The product of its (nonzero) digits is 400, while the sum is 19.

The square root of 21024055 is about 4585.1995594521. The cubic root of 21024055 is about 275.9977201730.

Adding to 21024055 its reverse (55042012), we get a palindrome (76066067).

The spelling of 21024055 in words is "twenty-one million, twenty-four thousand, fifty-five".