20821042 has 8 divisors (see below), whose sum is σ = 34070832. Its totient is φ = 9464100.

The previous prime is 20821037. The next prime is 20821051. The reversal of 20821042 is 24012802.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 473184 + ... + 473227.

It is an arithmetic number, because the mean of its divisors is an integer number (4258854).

Almost surely, 2^20821042 is an apocalyptic number.

20821042 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

20821042 is a deficient number, since it is larger than the sum of its proper divisors (13249790).

20821042 is a wasteful number, since it uses less digits than its factorization.

20821042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 946424.

The product of its (nonzero) digits is 256, while the sum is 19.

The square root of 20821042 is about 4563.0079991164. The cubic root of 20821042 is about 275.1064799778.

Adding to 20821042 its reverse (24012802), we get a palindrome (44833844).

The spelling of 20821042 in words is "twenty million, eight hundred twenty-one thousand, forty-two".