21385484 has 24 divisors (see below), whose sum is σ = 38229408. Its totient is φ = 10465280.

The previous prime is 21385471. The next prime is 21385513. The reversal of 21385484 is 48458312.

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, 72842 + ... + 73134.

It is an arithmetic number, because the mean of its divisors is an integer number (1592892).

Almost surely, 2^21385484 is an apocalyptic number.

It is an amenable number.

21385484 is a deficient number, since it is larger than the sum of its proper divisors (16843924).

21385484 is a wasteful number, since it uses less digits than its factorization.

21385484 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 625 (or 623 counting only the distinct ones).

The product of its digits is 30720, while the sum is 35.

The square root of 21385484 is about 4624.4441828181. Note that the first 3 decimals coincide. The cubic root of 21385484 is about 277.5703211661.

The spelling of 21385484 in words is "twenty-one million, three hundred eighty-five thousand, four hundred eighty-four".