13172220 has 120 divisors (see below), whose sum is σ = 42444864. Its totient is φ = 3417984.

The previous prime is 13172219. The next prime is 13172221. The reversal of 13172220 is 2227131.

It is an interprime number because it is at equal distance from previous prime (13172219) and next prime (13172221).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 13172193 and 13172202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13172221) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 76054 + ... + 76226.

Almost surely, 2^13172220 is an apocalyptic number.

13172220 is a gapful number since it is divisible by the number (10) 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 13172220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21222432).

13172220 is an abundant number, since it is smaller than the sum of its proper divisors (29272644).

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

13172220 is a wasteful number, since it uses less digits than its factorization.

13172220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 241 (or 230 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 18.

The square root of 13172220 is about 3629.3553146530. The cubic root of 13172220 is about 236.1672423666.

Adding to 13172220 its reverse (2227131), we get a palindrome (15399351).

The spelling of 13172220 in words is "thirteen million, one hundred seventy-two thousand, two hundred twenty".