21562560 has 84 divisors (see below), whose sum is σ = 74176128. Its totient is φ = 5749248.

The previous prime is 21562559. The next prime is 21562571. The reversal of 21562560 is 6526512.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 864 + ... + 6623.

Almost surely, 2^21562560 is an apocalyptic number.

21562560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21562560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37088064).

21562560 is an abundant number, since it is smaller than the sum of its proper divisors (52613568).

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

21562560 is a wasteful number, since it uses less digits than its factorization.

21562560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7510 (or 7497 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 21562560 is about 4643.5503658300. The cubic root of 21562560 is about 278.3343285449.

It can be divided in two parts, 21562 and 560, that added together give a palindrome (22122).

The spelling of 21562560 in words is "twenty-one million, five hundred sixty-two thousand, five hundred sixty".