21541442 has 8 divisors (see below), whose sum is σ = 34797756. Its totient is φ = 9942192.

The previous prime is 21541439. The next prime is 21541447. The reversal of 21541442 is 24414512.

It can be written as a sum of positive squares in 2 ways, for example, as 18913801 + 2627641 = 4349^2 + 1621^2 .

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

It is not an unprimeable number, because it can be changed into a prime (21541447) 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, 414233 + ... + 414284.

Almost surely, 2^21541442 is an apocalyptic number.

21541442 is a deficient number, since it is larger than the sum of its proper divisors (13256314).

21541442 is a wasteful number, since it uses less digits than its factorization.

21541442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 828532.

The product of its digits is 1280, while the sum is 23.

The square root of 21541442 is about 4641.2759021631. The cubic root of 21541442 is about 278.2434335818.

Adding to 21541442 its reverse (24414512), we get a palindrome (45955954).

The spelling of 21541442 in words is "twenty-one million, five hundred forty-one thousand, four hundred forty-two".