20217472 has 64 divisors (see below), whose sum is σ = 44724960. Its totient is φ = 9026560.

The previous prime is 20217467. The next prime is 20217479. The reversal of 20217472 is 27471202.

It is a tau number, because it is divible by the number of its divisors (64).

It is not an unprimeable number, because it can be changed into a prime (20217479) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 116778 + ... + 116950.

Almost surely, 2^20217472 is an apocalyptic number.

20217472 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20217472, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22362480).

20217472 is an abundant number, since it is smaller than the sum of its proper divisors (24507488).

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

20217472 is a wasteful number, since it uses less digits than its factorization.

20217472 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 281 (or 269 counting only the distinct ones).

The product of its (nonzero) digits is 1568, while the sum is 25.

The square root of 20217472 is about 4496.3843252106. The cubic root of 20217472 is about 272.4220667635.

Adding to 20217472 its reverse (27471202), we get a palindrome (47688674).

The spelling of 20217472 in words is "twenty million, two hundred seventeen thousand, four hundred seventy-two".