20522172 has 48 divisors (see below), whose sum is σ = 52762752. Its totient is φ = 6156480.

The previous prime is 20522149. The next prime is 20522197. The reversal of 20522172 is 27122502.

It is a happy number.

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, 13398 + ... + 14850.

It is an arithmetic number, because the mean of its divisors is an integer number (1099224).

Almost surely, 2^20522172 is an apocalyptic number.

20522172 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 20522172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26381376).

20522172 is an abundant number, since it is smaller than the sum of its proper divisors (32240580).

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

20522172 is a wasteful number, since it uses less digits than its factorization.

20522172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1578 (or 1576 counting only the distinct ones).

The product of its (nonzero) digits is 560, while the sum is 21.

The square root of 20522172 is about 4530.1403951754. The cubic root of 20522172 is about 273.7838172605.

Adding to 20522172 its reverse (27122502), we get a palindrome (47644674).

It can be divided in two parts, 2052 and 2172, that added together give a palindrome (4224).

The spelling of 20522172 in words is "twenty million, five hundred twenty-two thousand, one hundred seventy-two".