21369488 has 60 divisors (see below), whose sum is σ = 48832812. Its totient is φ = 9031680.

The previous prime is 21369473. The next prime is 21369499. The reversal of 21369488 is 88496312.

It can be written as a sum of positive squares in 2 ways, for example, as 12054784 + 9314704 = 3472^2 + 3052^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 75908 + ... + 76188.

Almost surely, 2^21369488 is an apocalyptic number.

21369488 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 21369488, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24416406).

21369488 is an abundant number, since it is smaller than the sum of its proper divisors (27463324).

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

21369488 is a wasteful number, since it uses less digits than its factorization.

21369488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 400 (or 387 counting only the distinct ones).

The product of its digits is 82944, while the sum is 41.

The square root of 21369488 is about 4622.7143541430. The cubic root of 21369488 is about 277.5010978503.

The spelling of 21369488 in words is "twenty-one million, three hundred sixty-nine thousand, four hundred eighty-eight".