21447192 has 64 divisors (see below), whose sum is σ = 58877280. Its totient is φ = 6469632.

The previous prime is 21447137. The next prime is 21447203. The reversal of 21447192 is 29174412.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15888 + ... + 17184.

Almost surely, 2^21447192 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 21447192, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29438640).

21447192 is an abundant number, since it is smaller than the sum of its proper divisors (37430088).

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

21447192 is a wasteful number, since it uses less digits than its factorization.

21447192 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1372 (or 1368 counting only the distinct ones).

The product of its digits is 4032, while the sum is 30.

The square root of 21447192 is about 4631.1113137129. Note that the first 3 decimals coincide. The cubic root of 21447192 is about 277.8370419802.

The spelling of 21447192 in words is "twenty-one million, four hundred forty-seven thousand, one hundred ninety-two".