1213625165 has 4 divisors (see below), whose sum is σ = 1456350204. Its totient is φ = 970900128.

The previous prime is 1213625159. The next prime is 1213625167. The reversal of 1213625165 is 5615263121.

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 146361604 + 1067263561 = 12098^2 + 32669^2 .

It is a cyclic number.

It is not a de Polignac number, because 1213625165 - 2²² = 1209430861 is a prime.

It is a super-2 number, since 2×1213625165² = 2945772082242554450, 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 (1213625167) 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, 121362512 + ... + 121362521.

It is an arithmetic number, because the mean of its divisors is an integer number (364087551).

Almost surely, 2^1213625165 is an apocalyptic number.

It is an amenable number.

1213625165 is a deficient number, since it is larger than the sum of its proper divisors (242725039).

1213625165 is an equidigital number, since it uses as much as digits as its factorization.

1213625165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 242725038.

The product of its digits is 10800, while the sum is 32.

The square root of 1213625165 is about 34837.1233743545. The cubic root of 1213625165 is about 1066.6653586681.

Adding to 1213625165 its reverse (5615263121), we get a palindrome (6828888286).

The spelling of 1213625165 in words is "one billion, two hundred thirteen million, six hundred twenty-five thousand, one hundred sixty-five".