21245042 has 16 divisors (see below), whose sum is σ = 39221952. Its totient is φ = 8404560.

The previous prime is 21245033. The next prime is 21245051. The reversal of 21245042 is 24054212.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21245033) and next prime (21245051).

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, 58184 + ... + 58547.

It is an arithmetic number, because the mean of its divisors is an integer number (2451372).

Almost surely, 2^21245042 is an apocalyptic number.

21245042 is a deficient number, since it is larger than the sum of its proper divisors (17976910).

21245042 is a wasteful number, since it uses less digits than its factorization.

21245042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116753.

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 21245042 is about 4609.2344266700. The cubic root of 21245042 is about 276.9613694950.

Adding to 21245042 its reverse (24054212), we get a palindrome (45299254).

It can be divided in two parts, 212 and 45042, that added together give a palindrome (45254).

The spelling of 21245042 in words is "twenty-one million, two hundred forty-five thousand, forty-two".