1287782841521 has 24 divisors (see below), whose sum is σ = 1477217431872. Its totient is φ = 1119676791200.

The previous prime is 1287782841493. The next prime is 1287782841563. The reversal of 1287782841521 is 1251482877821.

It is not a de Polignac number, because 1287782841521 - 2¹⁴ = 1287782825137 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1287785841521) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 28394555 + ... + 28439871.

It is an arithmetic number, because the mean of its divisors is an integer number (61550726328).

Almost surely, 2^{1287782841521} is an apocalyptic number.

1287782841521 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1287782841521 is a deficient number, since it is larger than the sum of its proper divisors (189434590351).

1287782841521 is a wasteful number, since it uses less digits than its factorization.

1287782841521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55573 (or 55562 counting only the distinct ones).

The product of its digits is 4014080, while the sum is 56.

The spelling of 1287782841521 in words is "one trillion, two hundred eighty-seven billion, seven hundred eighty-two million, eight hundred forty-one thousand, five hundred twenty-one".