21148416 has 108 divisors (see below), whose sum is σ = 62337912. Its totient is φ = 6893568.

The previous prime is 21148411. The next prime is 21148427. The reversal of 21148416 is 61484112.

It is a happy number.

It is a super-4 number, since 4×21148416⁴ (a number of 30 digits) contains 4444 as substring.

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 21148416.

It is not an unprimeable number, because it can be changed into a prime (21148411) 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, 154300 + ... + 154436.

Almost surely, 2^21148416 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 21148416, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31168956).

21148416 is an abundant number, since it is smaller than the sum of its proper divisors (41189496).

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

21148416 is a wasteful number, since it uses less digits than its factorization.

21148416 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226 (or 209 counting only the distinct ones).

The product of its digits is 1536, while the sum is 27.

The square root of 21148416 is about 4598.7406971909. The cubic root of 21148416 is about 276.5408424484.

The spelling of 21148416 in words is "twenty-one million, one hundred forty-eight thousand, four hundred sixteen".