21374400 has 168 divisors, whose sum is σ = 72251824. Its totient is φ = 5529600.

The previous prime is 21374399. The next prime is 21374443. The reversal of 21374400 is 447312.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 292764 + ... + 292836.

Almost surely, 2^21374400 is an apocalyptic number.

21374400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21374400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36125912).

21374400 is an abundant number, since it is smaller than the sum of its proper divisors (50877424).

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

21374400 is a wasteful number, since it uses less digits than its factorization.

21374400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159 (or 144 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 21.

The square root of 21374400 is about 4623.2456132029. The cubic root of 21374400 is about 277.5223583966.

The spelling of 21374400 in words is "twenty-one million, three hundred seventy-four thousand, four hundred".