1264784389440 has 448 divisors, whose sum is σ = 4784218048512. Its totient is φ = 279040204800.

The previous prime is 1264784389433. The next prime is 1264784389441. The reversal of 1264784389440 is 449834874621.

It is a super-2 number, since 2×1264784389440² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1264784389441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 9681999 + ... + 9811761.

It is an arithmetic number, because the mean of its divisors is an integer number (10679058144).

Almost surely, 2^{1264784389440} is an apocalyptic number.

1264784389440 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 1264784389440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2392109024256).

1264784389440 is an abundant number, since it is smaller than the sum of its proper divisors (3519433659072).

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

1264784389440 is a wasteful number, since it uses less digits than its factorization.

1264784389440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129878 (or 129868 counting only the distinct ones).

The product of its (nonzero) digits is 37158912, while the sum is 60.

The spelling of 1264784389440 in words is "one trillion, two hundred sixty-four billion, seven hundred eighty-four million, three hundred eighty-nine thousand, four hundred forty".