21452542 has 8 divisors (see below), whose sum is σ = 32295816. Its totient is φ = 10687272.

The previous prime is 21452533. The next prime is 21452549. The reversal of 21452542 is 24525412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21452549) 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, 18808 + ... + 19915.

It is an arithmetic number, because the mean of its divisors is an integer number (4036977).

Almost surely, 2^21452542 is an apocalyptic number.

21452542 is a deficient number, since it is larger than the sum of its proper divisors (10843274).

21452542 is a wasteful number, since it uses less digits than its factorization.

21452542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39002.

The product of its digits is 3200, while the sum is 25.

The square root of 21452542 is about 4631.6888928338. The cubic root of 21452542 is about 277.8601422007.

Adding to 21452542 its reverse (24525412), we get a palindrome (45977954).

The spelling of 21452542 in words is "twenty-one million, four hundred fifty-two thousand, five hundred forty-two".