21415248 has 60 divisors (see below), whose sum is σ = 60456448. Its totient is φ = 7076160.

The previous prime is 21415217. The next prime is 21415249. The reversal of 21415248 is 84251412.

21415248 is a `hidden beast` number, since 2 + 1 + 415 + 248 = 666.

It is a super-2 number, since 2×21415248² = 917225693803008, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21415249) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17703 + ... + 18873.

Almost surely, 2^21415248 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 21415248, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30228224).

21415248 is an abundant number, since it is smaller than the sum of its proper divisors (39041200).

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

21415248 is a wasteful number, since it uses less digits than its factorization.

21415248 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1312 (or 1303 counting only the distinct ones).

The product of its digits is 2560, while the sum is 27.

The square root of 21415248 is about 4627.6611803372. The cubic root of 21415248 is about 277.6990342253.

The spelling of 21415248 in words is "twenty-one million, four hundred fifteen thousand, two hundred forty-eight".