1287261931293 has 12 divisors (see below), whose sum is σ = 2002407448860. Its totient is φ = 792161188416.

The previous prime is 1287261931213. The next prime is 1287261931321. The reversal of 1287261931293 is 3921391627821.

1287261931293 is a `hidden beast` number, since 1 + 2 + 8 + 7 + 2 + 619 + 3 + 12 + 9 + 3 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 279008973369 + 1008252957924 = 528213^2 + 1004118^2 .

It is not a de Polignac number, because 1287261931293 - 2³⁸ = 1012384024349 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1287261931213) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5501119248 + ... + 5501119481.

It is an arithmetic number, because the mean of its divisors is an integer number (166867287405).

Almost surely, 2^{1287261931293} is an apocalyptic number.

1287261931293 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1287261931293 is a deficient number, since it is larger than the sum of its proper divisors (715145517567).

1287261931293 is a wasteful number, since it uses less digits than its factorization.

1287261931293 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11002238748 (or 11002238745 counting only the distinct ones).

The product of its digits is 1959552, while the sum is 54.

The spelling of 1287261931293 in words is "one trillion, two hundred eighty-seven billion, two hundred sixty-one million, nine hundred thirty-one thousand, two hundred ninety-three".