1265855011 has 2 divisors, whose sum is σ = 1265855012. Its totient is φ = 1265855010.

The previous prime is 1265854973. The next prime is 1265855029. The reversal of 1265855011 is 1105585621.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1265855011 - 2¹³ = 1265846819 is a prime.

It is not a weakly prime, because it can be changed into another prime (1265855711) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 632927505 + 632927506.

It is an arithmetic number, because the mean of its divisors is an integer number (632927506).

Almost surely, 2^1265855011 is an apocalyptic number.

1265855011 is a deficient number, since it is larger than the sum of its proper divisors (1).

1265855011 is an equidigital number, since it uses as much as digits as its factorization.

1265855011 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 12000, while the sum is 34.

The square root of 1265855011 is about 35578.8562351293. The cubic root of 1265855011 is about 1081.7527013201.

The spelling of 1265855011 in words is "one billion, two hundred sixty-five million, eight hundred fifty-five thousand, eleven".