1265140291 has 4 divisors (see below), whose sum is σ = 1265589072. Its totient is φ = 1264691512.

The previous prime is 1265140273. The next prime is 1265140301. The reversal of 1265140291 is 1920415621.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1265140291 - 2⁵ = 1265140259 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1265140271) 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, 220135 + ... + 225808.

It is an arithmetic number, because the mean of its divisors is an integer number (316397268).

Almost surely, 2^1265140291 is an apocalyptic number.

1265140291 is a deficient number, since it is larger than the sum of its proper divisors (448781).

1265140291 is an equidigital number, since it uses as much as digits as its factorization.

1265140291 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 448780.

The product of its (nonzero) digits is 4320, while the sum is 31.

The square root of 1265140291 is about 35568.8106492191. The cubic root of 1265140291 is about 1081.5490719312.

The spelling of 1265140291 in words is "one billion, two hundred sixty-five million, one hundred forty thousand, two hundred ninety-one".