1290551165 has 4 divisors (see below), whose sum is σ = 1548661404. Its totient is φ = 1032440928.

The previous prime is 1290551161. The next prime is 1290551179. The reversal of 1290551165 is 5611550921.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5611550921 = 21089 ⋅266089.

It can be written as a sum of positive squares in 2 ways, for example, as 711715684 + 578835481 = 26678^2 + 24059^2 .

It is a cyclic number.

It is not a de Polignac number, because 1290551165 - 2² = 1290551161 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 (1290551161) 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, 129055112 + ... + 129055121.

It is an arithmetic number, because the mean of its divisors is an integer number (387165351).

Almost surely, 2^1290551165 is an apocalyptic number.

It is an amenable number.

1290551165 is a deficient number, since it is larger than the sum of its proper divisors (258110239).

1290551165 is an equidigital number, since it uses as much as digits as its factorization.

1290551165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 258110238.

The product of its (nonzero) digits is 13500, while the sum is 35.

The square root of 1290551165 is about 35924.2420240149. The cubic root of 1290551165 is about 1088.7422478592.

The spelling of 1290551165 in words is "one billion, two hundred ninety million, five hundred fifty-one thousand, one hundred sixty-five".