1291644321340 has 24 divisors (see below), whose sum is σ = 2750656642272. Its totient is φ = 509380858560.

The previous prime is 1291644321301. The next prime is 1291644321377. The reversal of 1291644321340 is 431234461921.

It is a junction number, because it is equal to n+sod(n) for n = 1291644321293 and 1291644321302.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 454802919 + ... + 454805758.

It is an arithmetic number, because the mean of its divisors is an integer number (114610693428).

Almost surely, 2^{1291644321340} is an apocalyptic number.

1291644321340 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1291644321340 is an abundant number, since it is smaller than the sum of its proper divisors (1459012320932).

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

1291644321340 is a wasteful number, since it uses less digits than its factorization.

1291644321340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 909608757 (or 909608755 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 40.

The spelling of 1291644321340 in words is "one trillion, two hundred ninety-one billion, six hundred forty-four million, three hundred twenty-one thousand, three hundred forty".