21404152 has 32 divisors (see below), whose sum is σ = 50037120. Its totient is φ = 8339040.

The previous prime is 21404147. The next prime is 21404183. The reversal of 21404152 is 25140412.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 16758 + ... + 17989.

It is an arithmetic number, because the mean of its divisors is an integer number (1563660).

Almost surely, 2^21404152 is an apocalyptic number.

21404152 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21404152 is an abundant number, since it is smaller than the sum of its proper divisors (28632968).

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

21404152 is a wasteful number, since it uses less digits than its factorization.

21404152 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34771 (or 34767 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 19.

The square root of 21404152 is about 4626.4621472568. The cubic root of 21404152 is about 277.6510640310.

Adding to 21404152 its reverse (25140412), we get a palindrome (46544564).

The spelling of 21404152 in words is "twenty-one million, four hundred four thousand, one hundred fifty-two".