1265599112400 has 840 divisors, whose sum is σ = 5484459597120. Its totient is φ = 274046146560.

The previous prime is 1265599112377. The next prime is 1265599112411. The reversal of 1265599112400 is 42119955621.

1265599112400 is a `hidden beast` number, since 1 + 2 + 6 + 5 + 599 + 1 + 12 + 40 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (840).

It is a super-2 number, since 2×1265599112400² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 167 ways as a sum of consecutive naturals, for example, 38766484 + ... + 38799116.

It is an arithmetic number, because the mean of its divisors is an integer number (6529118568).

Almost surely, 2^{1265599112400} is an apocalyptic number.

1265599112400 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 1265599112400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2742229798560).

1265599112400 is an abundant number, since it is smaller than the sum of its proper divisors (4218860484720).

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

1265599112400 is a wasteful number, since it uses less digits than its factorization.

1265599112400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32695 (or 32669 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 45.

The spelling of 1265599112400 in words is "one trillion, two hundred sixty-five billion, five hundred ninety-nine million, one hundred twelve thousand, four hundred".