21024205 has 8 divisors (see below), whose sum is σ = 25816032. Its totient is φ = 16428048.

The previous prime is 21024197. The next prime is 21024209. The reversal of 21024205 is 50242012.

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 21024205 - 2³ = 21024197 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 (21024209) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 48679 + ... + 49108.

It is an arithmetic number, because the mean of its divisors is an integer number (3227004).

Almost surely, 2^21024205 is an apocalyptic number.

It is an amenable number.

21024205 is a deficient number, since it is larger than the sum of its proper divisors (4791827).

21024205 is an equidigital number, since it uses as much as digits as its factorization.

21024205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97835.

The product of its (nonzero) digits is 160, while the sum is 16.

The square root of 21024205 is about 4585.2159163991. The cubic root of 21024205 is about 275.9983765570.

Adding to 21024205 its reverse (50242012), we get a palindrome (71266217).

It can be divided in two parts, 2102 and 4205, that multiplied together give a triangular number (8838910 = T₄₂₀₄).

The spelling of 21024205 in words is "twenty-one million, twenty-four thousand, two hundred five".