1225181 has 4 divisors (see below), whose sum is σ = 1258332. Its totient is φ = 1192032.

The previous prime is 1225157. The next prime is 1225183. The reversal of 1225181 is 1815221.

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 722500 + 502681 = 850^2 + 709^2 .

It is a cyclic number.

It is not a de Polignac number, because 1225181 - 2⁶ = 1225117 is a prime.

It is a super-2 number, since 2×1225181² = 3002136965522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1225183) 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, 16520 + ... + 16593.

It is an arithmetic number, because the mean of its divisors is an integer number (314583).

2^1225181 is an apocalyptic number.

It is an amenable number.

1225181 is a deficient number, since it is larger than the sum of its proper divisors (33151).

1225181 is an equidigital number, since it uses as much as digits as its factorization.

1225181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33150.

The product of its digits is 160, while the sum is 20.

The square root of 1225181 is about 1106.8789455040. The cubic root of 1225181 is about 107.0040176673.

The spelling of 1225181 in words is "one million, two hundred twenty-five thousand, one hundred eighty-one".