21167244 has 168 divisors, whose sum is σ = 68308128. Its totient is φ = 5598720.

The previous prime is 21167239. The next prime is 21167257. The reversal of 21167244 is 44276112.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

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

It is an unprimeable number.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 346974 + ... + 347034.

It is an arithmetic number, because the mean of its divisors is an integer number (406596).

Almost surely, 2^21167244 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 21167244, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34154064).

21167244 is an abundant number, since it is smaller than the sum of its proper divisors (47140884).

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

21167244 is a wasteful number, since it uses less digits than its factorization.

21167244 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107 (or 90 counting only the distinct ones).

The product of its digits is 2688, while the sum is 27.

The square root of 21167244 is about 4600.7873239262. The cubic root of 21167244 is about 276.6228843155.

Adding to 21167244 its sum of digits (27), we get a triangular number (21167271 = T₆₅₀₆).

The spelling of 21167244 in words is "twenty-one million, one hundred sixty-seven thousand, two hundred forty-four".