2172157 has 6 divisors (see below), whose sum is σ = 2352282. Its totient is φ = 2004912.

The previous prime is 2172151. The next prime is 2172161. The reversal of 2172157 is 7512712.

It is a happy number.

2172157 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 37636 + 2134521 = 194^2 + 1461^2 .

It is not a de Polignac number, because 2172157 - 2¹¹ = 2170109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2172151) 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 5 ways as a sum of consecutive naturals, for example, 6258 + ... + 6595.

It is an arithmetic number, because the mean of its divisors is an integer number (392047).

2^2172157 is an apocalyptic number.

It is an amenable number.

2172157 is a deficient number, since it is larger than the sum of its proper divisors (180125).

2172157 is a wasteful number, since it uses less digits than its factorization.

2172157 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12879 (or 12866 counting only the distinct ones).

The product of its digits is 980, while the sum is 25.

The square root of 2172157 is about 1473.8239379247. The cubic root of 2172157 is about 129.5081413863.

Adding to 2172157 its reverse (7512712), we get a palindrome (9684869).

The spelling of 2172157 in words is "two million, one hundred seventy-two thousand, one hundred fifty-seven".