1265641653 has 8 divisors (see below), whose sum is σ = 1786788288. Its totient is φ = 794128064.

The previous prime is 1265641651. The next prime is 1265641717. The reversal of 1265641653 is 3561465621.

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 1265641653 - 2¹ = 1265641651 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1265641651) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12408201 + ... + 12408302.

It is an arithmetic number, because the mean of its divisors is an integer number (223348536).

Almost surely, 2^1265641653 is an apocalyptic number.

It is an amenable number.

1265641653 is a deficient number, since it is larger than the sum of its proper divisors (521146635).

1265641653 is a wasteful number, since it uses less digits than its factorization.

1265641653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24816523.

The product of its digits is 129600, while the sum is 39.

The square root of 1265641653 is about 35575.8577268349. The cubic root of 1265641653 is about 1081.6919219630.

The spelling of 1265641653 in words is "one billion, two hundred sixty-five million, six hundred forty-one thousand, six hundred fifty-three".