1257338717261 has 8 divisors (see below), whose sum is σ = 1379570806944. Its totient is φ = 1136428055920.

The previous prime is 1257338717191. The next prime is 1257338717287. The reversal of 1257338717261 is 1627178337521.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1257338717261 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1257338711261) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 330355091 + ... + 330358896.

It is an arithmetic number, because the mean of its divisors is an integer number (172446350868).

Almost surely, 2^{1257338717261} is an apocalyptic number.

1257338717261 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1257338717261 is a deficient number, since it is larger than the sum of its proper divisors (122232089683).

1257338717261 is a wasteful number, since it uses less digits than its factorization.

1257338717261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 660714171.

The product of its digits is 2963520, while the sum is 53.

The spelling of 1257338717261 in words is "one trillion, two hundred fifty-seven billion, three hundred thirty-eight million, seven hundred seventeen thousand, two hundred sixty-one".