21019488 has 96 divisors (see below), whose sum is σ = 65157120. Its totient is φ = 5806080.

The previous prime is 21019487. The next prime is 21019541. The reversal of 21019488 is 88491012.

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21019487) 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, 20328 + ... + 21336.

It is an arithmetic number, because the mean of its divisors is an integer number (678720).

Almost surely, 2^21019488 is an apocalyptic number.

21019488 is a gapful number since it is divisible by the number (28) 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 21019488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32578560).

21019488 is an abundant number, since it is smaller than the sum of its proper divisors (44137632).

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

21019488 is a wasteful number, since it uses less digits than its factorization.

21019488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1060 (or 1052 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 33.

The square root of 21019488 is about 4584.7015170020. The cubic root of 21019488 is about 275.9777339736.

The spelling of 21019488 in words is "twenty-one million, nineteen thousand, four hundred eighty-eight".