21040046 has 8 divisors (see below), whose sum is σ = 32155704. Its totient is φ = 10321480.

The previous prime is 21040043. The next prime is 21040057. The reversal of 21040046 is 64004012.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21040043) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 99140 + ... + 99351.

It is an arithmetic number, because the mean of its divisors is an integer number (4019463).

Almost surely, 2^21040046 is an apocalyptic number.

21040046 is a deficient number, since it is larger than the sum of its proper divisors (11115658).

21040046 is a wasteful number, since it uses less digits than its factorization.

21040046 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198546.

The product of its (nonzero) digits is 192, while the sum is 17.

The square root of 21040046 is about 4586.9429907074. The cubic root of 21040046 is about 276.0676775154.

Adding to 21040046 its reverse (64004012), we get a palindrome (85044058).

The spelling of 21040046 in words is "twenty-one million, forty thousand, forty-six".