21536042 has 32 divisors (see below), whose sum is σ = 37791360. Its totient is φ = 9095680.

The previous prime is 21536033. The next prime is 21536069. The reversal of 21536042 is 24063512.

It is a super-2 number, since 2×21536042² = 927602210051528, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21535999 and 21536017.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 32963 + ... + 33609.

It is an arithmetic number, because the mean of its divisors is an integer number (1180980).

Almost surely, 2^21536042 is an apocalyptic number.

21536042 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

21536042 is a deficient number, since it is larger than the sum of its proper divisors (16255318).

21536042 is a wasteful number, since it uses less digits than its factorization.

21536042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 766.

The product of its (nonzero) digits is 1440, while the sum is 23.

The square root of 21536042 is about 4640.6941291147. The cubic root of 21536042 is about 278.2201816548.

Adding to 21536042 its reverse (24063512), we get a palindrome (45599554).

The spelling of 21536042 in words is "twenty-one million, five hundred thirty-six thousand, forty-two".