21447450 has 48 divisors (see below), whose sum is σ = 59103360. Its totient is φ = 5718960.

The previous prime is 21447427. The next prime is 21447509. The reversal of 21447450 is 5474412.

It is a super-2 number, since 2×21447450² = 919986223005000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

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 23 ways as a sum of consecutive naturals, for example, 6594 + ... + 9293.

It is an arithmetic number, because the mean of its divisors is an integer number (1231320).

Almost surely, 2^21447450 is an apocalyptic number.

21447450 is an abundant number, since it is smaller than the sum of its proper divisors (37655910).

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

21447450 is a wasteful number, since it uses less digits than its factorization.

21447450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15908 (or 15897 counting only the distinct ones).

The product of its (nonzero) digits is 4480, while the sum is 27.

The square root of 21447450 is about 4631.1391687143. The cubic root of 21447450 is about 277.8381560603.

The spelling of 21447450 in words is "twenty-one million, four hundred forty-seven thousand, four hundred fifty".