21386548 has 12 divisors (see below), whose sum is σ = 37797732. Its totient is φ = 10587200.

The previous prime is 21386531. The next prime is 21386557. The reversal of 21386548 is 84568312.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 18421264 + 2965284 = 4292^2 + 1722^2 .

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 26065 + ... + 26872.

It is an arithmetic number, because the mean of its divisors is an integer number (3149811).

Almost surely, 2^21386548 is an apocalyptic number.

It is an amenable number.

21386548 is a deficient number, since it is larger than the sum of its proper divisors (16411184).

21386548 is a wasteful number, since it uses less digits than its factorization.

21386548 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53042 (or 53040 counting only the distinct ones).

The product of its digits is 46080, while the sum is 37.

The square root of 21386548 is about 4624.5592222395. The cubic root of 21386548 is about 277.5749244431.

The spelling of 21386548 in words is "twenty-one million, three hundred eighty-six thousand, five hundred forty-eight".