21404046 has 16 divisors (see below), whose sum is σ = 43510608. Its totient is φ = 7017600.

The previous prime is 21404029. The next prime is 21404063. The reversal of 21404046 is 64040412.

It is an interprime number because it is at equal distance from previous prime (21404029) and next prime (21404063).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28875 + ... + 29606.

It is an arithmetic number, because the mean of its divisors is an integer number (2719413).

Almost surely, 2^21404046 is an apocalyptic number.

21404046 is an abundant number, since it is smaller than the sum of its proper divisors (22106562).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21404046 is a wasteful number, since it uses less digits than its factorization.

21404046 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58547.

The product of its (nonzero) digits is 768, while the sum is 21.

The square root of 21404046 is about 4626.4506914048. The cubic root of 21404046 is about 277.6506056922.

Adding to 21404046 its reverse (64040412), we get a palindrome (85444458).

The spelling of 21404046 in words is "twenty-one million, four hundred four thousand, forty-six".