21219748 has 48 divisors (see below), whose sum is σ = 42835968. Its totient is φ = 9108000.

The previous prime is 21219727. The next prime is 21219749. The reversal of 21219748 is 84791212.

It is not an unprimeable number, because it can be changed into a prime (21219749) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 63943 + ... + 64273.

It is an arithmetic number, because the mean of its divisors is an integer number (892416).

Almost surely, 2^21219748 is an apocalyptic number.

It is an amenable number.

21219748 is an abundant number, since it is smaller than the sum of its proper divisors (21616220).

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

21219748 is a wasteful number, since it uses less digits than its factorization.

21219748 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 424 (or 422 counting only the distinct ones).

The product of its digits is 8064, while the sum is 34.

The square root of 21219748 is about 4606.4897698790. The cubic root of 21219748 is about 276.8514106174.

The spelling of 21219748 in words is "twenty-one million, two hundred nineteen thousand, seven hundred forty-eight".