21063580 has 12 divisors (see below), whose sum is σ = 44233560. Its totient is φ = 8425424.

The previous prime is 21063569. The next prime is 21063673. The reversal of 21063580 is 8536012.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 526570 + ... + 526609.

It is an arithmetic number, because the mean of its divisors is an integer number (3686130).

Almost surely, 2^21063580 is an apocalyptic number.

21063580 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21063580 is an abundant number, since it is smaller than the sum of its proper divisors (23169980).

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

21063580 is a wasteful number, since it uses less digits than its factorization.

21063580 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1053188 (or 1053186 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 21063580 is about 4589.5075988607. The cubic root of 21063580 is about 276.1705694937.

Adding to 21063580 its reverse (8536012), we get a palindrome (29599592).

The spelling of 21063580 in words is "twenty-one million, sixty-three thousand, five hundred eighty".