21007488 has 64 divisors (see below), whose sum is σ = 56279520. Its totient is φ = 6942720.

The previous prime is 21007463. The next prime is 21007499. The reversal of 21007488 is 88470012.

It is a tau number, because it is divible by the number of its divisors (64).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 87048 + ... + 87288.

Almost surely, 2^21007488 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 21007488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28139760).

21007488 is an abundant number, since it is smaller than the sum of its proper divisors (35272032).

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

21007488 is a wasteful number, since it uses less digits than its factorization.

21007488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 485 (or 473 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 30.

The square root of 21007488 is about 4583.3926299195. The cubic root of 21007488 is about 275.9252055258.

It can be divided in two parts, 2 and 1007488, that added together give a triangular number (1007490 = T₁₄₁₉).

The spelling of 21007488 in words is "twenty-one million, seven thousand, four hundred eighty-eight".