1257913556689 has 4 divisors (see below), whose sum is σ = 1301289886260. Its totient is φ = 1214537227120.

The previous prime is 1257913556659. The next prime is 1257913556693. The reversal of 1257913556689 is 9866553197521.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 716548706064 + 541364850625 = 846492^2 + 735775^2 .

It is a cyclic number.

It is not a de Polignac number, because 1257913556689 - 2⁷ = 1257913556561 is a prime.

It is a super-2 number, since 2×1257913556689² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1257913556609) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21688164742 + ... + 21688164799.

It is an arithmetic number, because the mean of its divisors is an integer number (325322471565).

Almost surely, 2^{1257913556689} is an apocalyptic number.

It is an amenable number.

1257913556689 is a deficient number, since it is larger than the sum of its proper divisors (43376329571).

1257913556689 is an equidigital number, since it uses as much as digits as its factorization.

1257913556689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43376329570.

The product of its digits is 122472000, while the sum is 67.

The spelling of 1257913556689 in words is "one trillion, two hundred fifty-seven billion, nine hundred thirteen million, five hundred fifty-six thousand, six hundred eighty-nine".