1265321745 has 24 divisors (see below), whose sum is σ = 2252503656. Its totient is φ = 656598528.

The previous prime is 1265321737. The next prime is 1265321753. The reversal of 1265321745 is 5471235621.

1265321745 is a `hidden beast` number, since 1 + 265 + 321 + 74 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (1265321737) and next prime (1265321753).

It can be written as a sum of positive squares in 4 ways, for example, as 130507776 + 1134813969 = 11424^2 + 33687^2 .

It is not a de Polignac number, because 1265321745 - 2³ = 1265321737 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 378312 + ... + 381641.

It is an arithmetic number, because the mean of its divisors is an integer number (93854319).

Almost surely, 2^1265321745 is an apocalyptic number.

1265321745 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1265321745 is a deficient number, since it is larger than the sum of its proper divisors (987181911).

1265321745 is a wasteful number, since it uses less digits than its factorization.

1265321745 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 760001 (or 759998 counting only the distinct ones).

The product of its digits is 50400, while the sum is 36.

The square root of 1265321745 is about 35571.3613037230. The cubic root of 1265321745 is about 1081.6007768751.

The spelling of 1265321745 in words is "one billion, two hundred sixty-five million, three hundred twenty-one thousand, seven hundred forty-five".