21013042 has 8 divisors (see below), whose sum is σ = 32190336. Its totient is φ = 10282932.

The previous prime is 21013021. The next prime is 21013043. The reversal of 21013042 is 24031012.

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 (21013043) 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, 111678 + ... + 111865.

It is an arithmetic number, because the mean of its divisors is an integer number (4023792).

Almost surely, 2^21013042 is an apocalyptic number.

21013042 is a deficient number, since it is larger than the sum of its proper divisors (11177294).

21013042 is a wasteful number, since it uses less digits than its factorization.

21013042 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 223592.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 21013042 is about 4583.9984729491. The cubic root of 21013042 is about 275.9495199284.

Adding to 21013042 its reverse (24031012), we get a palindrome (45044054).

The spelling of 21013042 in words is "twenty-one million, thirteen thousand, forty-two".