1265123503 has 12 divisors (see below), whose sum is σ = 1474977600. Its totient is φ = 1081957632.

The previous prime is 1265123477. The next prime is 1265123537. The reversal of 1265123503 is 3053215621.

It is not a de Polignac number, because 1265123503 - 2⁵ = 1265123471 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 (1265123543) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6751 + ... + 50752.

It is an arithmetic number, because the mean of its divisors is an integer number (122914800).

Almost surely, 2^1265123503 is an apocalyptic number.

1265123503 is a deficient number, since it is larger than the sum of its proper divisors (209854097).

1265123503 is an equidigital number, since it uses as much as digits as its factorization.

1265123503 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57966 (or 57959 counting only the distinct ones).

The product of its (nonzero) digits is 5400, while the sum is 28.

The square root of 1265123503 is about 35568.5746551644. The cubic root of 1265123503 is about 1081.5442879753.

The spelling of 1265123503 in words is "one billion, two hundred sixty-five million, one hundred twenty-three thousand, five hundred three".