1040644035440 has 80 divisors (see below), whose sum is σ = 2536149613536. Its totient is φ = 396660633600.

The previous prime is 1040644035439. The next prime is 1040644035491. The reversal of 1040644035440 is 445304460401.

It is a tau number, because it is divible by the number of its divisors (80).

It is a self number, because there is not a number n which added to its sum of digits gives 1040644035440.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3548141 + ... + 3830220.

Almost surely, 2^{1040644035440} is an apocalyptic number.

1040644035440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1040644035440 is an abundant number, since it is smaller than the sum of its proper divisors (1495505578096).

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

1040644035440 is a wasteful number, since it uses less digits than its factorization.

1040644035440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7378458 (or 7378452 counting only the distinct ones).

The product of its (nonzero) digits is 92160, while the sum is 35.

Adding to 1040644035440 its reverse (445304460401), we get a palindrome (1485948495841).

The spelling of 1040644035440 in words is "one trillion, forty billion, six hundred forty-four million, thirty-five thousand, four hundred forty".