21220488 has 64 divisors (see below), whose sum is σ = 62424000. Its totient is φ = 6656256.

The previous prime is 21220487. The next prime is 21220501. The reversal of 21220488 is 88402212.

It is a super-2 number, since 2×21220488² = 900618221916288, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (21220487) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 783 + ... + 6561.

It is an arithmetic number, because the mean of its divisors is an integer number (975375).

Almost surely, 2^21220488 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21220488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31212000).

21220488 is an abundant number, since it is smaller than the sum of its proper divisors (41203512).

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

21220488 is a wasteful number, since it uses less digits than its factorization.

21220488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5811 (or 5801 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 27.

The square root of 21220488 is about 4606.5700906423. The cubic root of 21220488 is about 276.8546288093.

The spelling of 21220488 in words is "twenty-one million, two hundred twenty thousand, four hundred eighty-eight".