21497112 has 192 divisors, whose sum is σ = 76265280. Its totient is φ = 5308416.

The previous prime is 21497101. The next prime is 21497123. The reversal of 21497112 is 21179412.

It is an interprime number because it is at equal distance from previous prime (21497101) and next prime (21497123).

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

It is a zygodrome in base 3.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 111288 + ... + 111480.

It is an arithmetic number, because the mean of its divisors is an integer number (397215).

Almost surely, 2^21497112 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 21497112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38132640).

21497112 is an abundant number, since it is smaller than the sum of its proper divisors (54768168).

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

21497112 is a wasteful number, since it uses less digits than its factorization.

21497112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242 (or 235 counting only the distinct ones).

The product of its digits is 1008, while the sum is 27.

The square root of 21497112 is about 4636.4978162402. The cubic root of 21497112 is about 278.0524373593.

It can be divided in two parts, 21497 and 112, that added together give a square (21609 = 147²).

The spelling of 21497112 in words is "twenty-one million, four hundred ninety-seven thousand, one hundred twelve".