1265565536 has 24 divisors (see below), whose sum is σ = 2532431664. Its totient is φ = 622408320.

The previous prime is 1265565463. The next prime is 1265565571. The reversal of 1265565536 is 6355655621.

It is a super-2 number, since 2×1265565536² = 3203312251821934592, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 322220 + ... + 326123.

It is an arithmetic number, because the mean of its divisors is an integer number (105517986).

Almost surely, 2^1265565536 is an apocalyptic number.

1265565536 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1265565536 is an abundant number, since it is smaller than the sum of its proper divisors (1266866128).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1265565536 is an equidigital number, since it uses as much as digits as its factorization.

1265565536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 648414 (or 648406 counting only the distinct ones).

The product of its digits is 810000, while the sum is 44.

The square root of 1265565536 is about 35574.7879262828. The cubic root of 1265565536 is about 1081.6702368374.

The spelling of 1265565536 in words is "one billion, two hundred sixty-five million, five hundred sixty-five thousand, five hundred thirty-six".