1265401036420 has 24 divisors (see below), whose sum is σ = 2657409844824. Its totient is φ = 506147525376.

The previous prime is 1265401036391. The next prime is 1265401036423. The reversal of 1265401036420 is 246301045621.

It can be written as a sum of positive squares in 4 ways, for example, as 163942390404 + 1101458646016 = 404898^2 + 1049504^2 .

It is not an unprimeable number, because it can be changed into a prime (1265401036423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20104 + ... + 1590976.

It is an arithmetic number, because the mean of its divisors is an integer number (110725410201).

Almost surely, 2^{1265401036420} is an apocalyptic number.

1265401036420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1265401036420 is an abundant number, since it is smaller than the sum of its proper divisors (1392008808404).

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

1265401036420 is a wasteful number, since it uses less digits than its factorization.

1265401036420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1611159 (or 1611157 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 34.

The spelling of 1265401036420 in words is "one trillion, two hundred sixty-five billion, four hundred one million, thirty-six thousand, four hundred twenty".