21110042 has 8 divisors (see below), whose sum is σ = 31696500. Its totient is φ = 10544544.

The previous prime is 21110041. The next prime is 21110051. The reversal of 21110042 is 24001112.

It can be written as a sum of positive squares in 2 ways, for example, as 21077281 + 32761 = 4591^2 + 181^2 .

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 (21110041) 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, 2417 + ... + 6932.

Almost surely, 2^21110042 is an apocalyptic number.

21110042 is a deficient number, since it is larger than the sum of its proper divisors (10586458).

21110042 is a wasteful number, since it uses less digits than its factorization.

21110042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10480.

The product of its (nonzero) digits is 16, while the sum is 11.

The square root of 21110042 is about 4594.5665736824. The cubic root of 21110042 is about 276.3734791925.

Adding to 21110042 its reverse (24001112), we get a palindrome (45111154).

The spelling of 21110042 in words is "twenty-one million, one hundred ten thousand, forty-two".