65172220 has 48 divisors (see below), whose sum is σ = 146397888. Its totient is φ = 24284160.

The previous prime is 65172187. The next prime is 65172229. The reversal of 65172220 is 2227156.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65172229) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34090 + ... + 35950.

It is an arithmetic number, because the mean of its divisors is an integer number (3049956).

Almost surely, 2^65172220 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 65172220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (73198944).

65172220 is an abundant number, since it is smaller than the sum of its proper divisors (81225668).

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

65172220 is a wasteful number, since it uses less digits than its factorization.

65172220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1990 (or 1988 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 65172220 is about 8072.9313139652. The cubic root of 65172220 is about 402.4273649521.

Adding to 65172220 its reverse (2227156), we get a palindrome (67399376).

The spelling of 65172220 in words is "sixty-five million, one hundred seventy-two thousand, two hundred twenty".