1265606645 has 8 divisors (see below), whose sum is σ = 1559774904. Its totient is φ = 985120704.

The previous prime is 1265606609. The next prime is 1265606653. The reversal of 1265606645 is 5466065621.

It can be written as a sum of positive squares in 4 ways, for example, as 338891281 + 926715364 = 18409^2 + 30442^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1265606645 - 2⁸ = 1265606389 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3420374 + ... + 3420743.

It is an arithmetic number, because the mean of its divisors is an integer number (194971863).

Almost surely, 2^1265606645 is an apocalyptic number.

It is an amenable number.

1265606645 is a deficient number, since it is larger than the sum of its proper divisors (294168259).

1265606645 is an equidigital number, since it uses as much as digits as its factorization.

1265606645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6841159.

The product of its (nonzero) digits is 259200, while the sum is 41.

The square root of 1265606645 is about 35575.3657043747. The cubic root of 1265606645 is about 1081.6819485713.

The spelling of 1265606645 in words is "one billion, two hundred sixty-five million, six hundred six thousand, six hundred forty-five".