21648546 has 20 divisors (see below), whose sum is σ = 48509142. Its totient is φ = 7216128.

The previous prime is 21648541. The next prime is 21648551. The reversal of 21648546 is 64584612.

21648546 is a `hidden beast` number, since 2 + 1 + 648 + 5 + 4 + 6 = 666.

It is an interprime number because it is at equal distance from previous prime (21648541) and next prime (21648551).

It can be written as a sum of positive squares in only one way, i.e., 19053225 + 2595321 = 4365^2 + 1611^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21648546.

It is not an unprimeable number, because it can be changed into a prime (21648541) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 66655 + ... + 66978.

Almost surely, 2^21648546 is an apocalyptic number.

21648546 is an abundant number, since it is smaller than the sum of its proper divisors (26860596).

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

21648546 is a wasteful number, since it uses less digits than its factorization.

21648546 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133647 (or 133638 counting only the distinct ones).

The product of its digits is 46080, while the sum is 36.

The square root of 21648546 is about 4652.7998022696. The cubic root of 21648546 is about 278.7038133240.

The spelling of 21648546 in words is "twenty-one million, six hundred forty-eight thousand, five hundred forty-six".