1331940464640 has 864 divisors, whose sum is σ = 4955528607120. Its totient is φ = 343109468160.

The previous prime is 1331940464633. The next prime is 1331940464641. The reversal of 1331940464640 is 464640491331.

1331940464640 is a `hidden beast` number, since 13 + 31 + 94 + 0 + 464 + 64 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (864).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1331940464641) 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 71 ways as a sum of consecutive naturals, for example, 2391275242 + ... + 2391275798.

Almost surely, 2^{1331940464640} is an apocalyptic number.

1331940464640 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 1331940464640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2477764303560).

1331940464640 is an abundant number, since it is smaller than the sum of its proper divisors (3623588142480).

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

1331940464640 is an frugal number, since it uses more digits than its factorization.

1331940464640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 661 (or 598 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 45.

The spelling of 1331940464640 in words is "one trillion, three hundred thirty-one billion, nine hundred forty million, four hundred sixty-four thousand, six hundred forty".