20171172 has 48 divisors (see below), whose sum is σ = 54010880. Its totient is φ = 5739552.

The previous prime is 20171147. The next prime is 20171189. The reversal of 20171172 is 27117102.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (21).

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, 36603 + ... + 37149.

Almost surely, 2^20171172 is an apocalyptic number.

It is an amenable number.

20171172 is an abundant number, since it is smaller than the sum of its proper divisors (33839708).

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

20171172 is a wasteful number, since it uses less digits than its factorization.

20171172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1000 (or 998 counting only the distinct ones).

The product of its (nonzero) digits is 196, while the sum is 21.

The square root of 20171172 is about 4491.2327928977. The cubic root of 20171172 is about 272.2139500348.

Adding to 20171172 its reverse (27117102), we get a palindrome (47288274).

The spelling of 20171172 in words is "twenty million, one hundred seventy-one thousand, one hundred seventy-two".