1263438487557 has 12 divisors (see below), whose sum is σ = 1921017583680. Its totient is φ = 797961149928.

The previous prime is 1263438487543. The next prime is 1263438487583. The reversal of 1263438487557 is 7557848343621.

It is a happy number.

1263438487557 is a `hidden beast` number, since 1 + 2 + 6 + 3 + 4 + 38 + 48 + 7 + 557 = 666.

It is not a de Polignac number, because 1263438487557 - 2⁴ = 1263438487541 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1263438487494 and 1263438487503.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1263438487057) 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, 3694264413 + ... + 3694264754.

It is an arithmetic number, because the mean of its divisors is an integer number (160084798640).

Almost surely, 2^{1263438487557} is an apocalyptic number.

It is an amenable number.

1263438487557 is a deficient number, since it is larger than the sum of its proper divisors (657579096123).

1263438487557 is a wasteful number, since it uses less digits than its factorization.

1263438487557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7388529192 (or 7388529189 counting only the distinct ones).

The product of its digits is 135475200, while the sum is 63.

The spelling of 1263438487557 in words is "one trillion, two hundred sixty-three billion, four hundred thirty-eight million, four hundred eighty-seven thousand, five hundred fifty-seven".