1265539472640 has 288 divisors, whose sum is σ = 4645769990400. Its totient is φ = 325839790080.

The previous prime is 1265539472633. The next prime is 1265539472653. The reversal of 1265539472640 is 462749355621.

It is a happy number.

1265539472640 is a `hidden beast` number, since 1 + 2 + 6 + 5 + 539 + 47 + 2 + 64 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 370885 + ... + 1633595.

It is an arithmetic number, because the mean of its divisors is an integer number (16131145800).

Almost surely, 2^{1265539472640} is an apocalyptic number.

1265539472640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1265539472640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2322884995200).

1265539472640 is an abundant number, since it is smaller than the sum of its proper divisors (3380230517760).

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

1265539472640 is a wasteful number, since it uses less digits than its factorization.

1265539472640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1262770 (or 1262750 counting only the distinct ones).

The product of its (nonzero) digits is 10886400, while the sum is 54.

The spelling of 1265539472640 in words is "one trillion, two hundred sixty-five billion, five hundred thirty-nine million, four hundred seventy-two thousand, six hundred forty".