21400324 has 24 divisors (see below), whose sum is σ = 41138496. Its totient is φ = 9660000.

The previous prime is 21400277. The next prime is 21400343. The reversal of 21400324 is 42300412.

It is a junction number, because it is equal to n+sod(n) for n = 21400298 and 21400307.

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, 5034 + ... + 8254.

It is an arithmetic number, because the mean of its divisors is an integer number (1714104).

Almost surely, 2^21400324 is an apocalyptic number.

It is an amenable number.

21400324 is a deficient number, since it is larger than the sum of its proper divisors (19738172).

21400324 is a wasteful number, since it uses less digits than its factorization.

21400324 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3387 (or 3385 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 21400324 is about 4626.0484217094. The cubic root of 21400324 is about 277.6345109865.

Adding to 21400324 its reverse (42300412), we get a palindrome (63700736).

The spelling of 21400324 in words is "twenty-one million, four hundred thousand, three hundred twenty-four".