21489474 has 8 divisors (see below), whose sum is σ = 42978960. Its totient is φ = 7163156.

The previous prime is 21489469. The next prime is 21489491. The reversal of 21489474 is 47498412.

It is a sphenic number, since it is the product of 3 distinct primes.

21489474 is an admirable 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 3 ways as a sum of consecutive naturals, for example, 1790784 + ... + 1790795.

It is an arithmetic number, because the mean of its divisors is an integer number (5372370).

Almost surely, 2^21489474 is an apocalyptic number.

21489474 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21489474 is a wasteful number, since it uses less digits than its factorization.

21489474 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3581584.

The product of its digits is 64512, while the sum is 39.

The square root of 21489474 is about 4635.6740610185. The cubic root of 21489474 is about 278.0195024532.

The spelling of 21489474 in words is "twenty-one million, four hundred eighty-nine thousand, four hundred seventy-four".