2145217 has 4 divisors (see below), whose sum is σ = 2219220. Its totient is φ = 2071216.

The previous prime is 2145197. The next prime is 2145239. The reversal of 2145217 is 7125412.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1354896 + 790321 = 1164^2 + 889^2 .

It is a cyclic number.

It is not a de Polignac number, because 2145217 - 2⁷ = 2145089 is a prime.

It is a Duffinian number.

2145217 is a lucky number.

It is a nialpdrome in base 12.

It is a zygodrome in base 3.

It is not an unprimeable number, because it can be changed into a prime (2145277) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36958 + ... + 37015.

It is an arithmetic number, because the mean of its divisors is an integer number (554805).

2^2145217 is an apocalyptic number.

It is an amenable number.

2145217 is a deficient number, since it is larger than the sum of its proper divisors (74003).

2145217 is an equidigital number, since it uses as much as digits as its factorization.

2145217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 74002.

The product of its digits is 560, while the sum is 22.

The square root of 2145217 is about 1464.6559322926. The cubic root of 2145217 is about 128.9705078505.

The spelling of 2145217 in words is "two million, one hundred forty-five thousand, two hundred seventeen".