1557208683931 has 2 divisors, whose sum is σ = 1557208683932. Its totient is φ = 1557208683930.

The previous prime is 1557208683929. The next prime is 1557208684001. The reversal of 1557208683931 is 1393868027551.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (1393868027551) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1557208683931 - 2¹ = 1557208683929 is a prime.

It is a super-2 number, since 2×1557208683931² (a number of 25 digits) contains 22 as substring.

Together with 1557208683929, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1557208683731) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 778604341965 + 778604341966.

It is an arithmetic number, because the mean of its divisors is an integer number (778604341966).

Almost surely, 2^{1557208683931} is an apocalyptic number.

1557208683931 is a deficient number, since it is larger than the sum of its proper divisors (1).

1557208683931 is an equidigital number, since it uses as much as digits as its factorization.

1557208683931 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10886400, while the sum is 58.

The spelling of 1557208683931 in words is "one trillion, five hundred fifty-seven billion, two hundred eight million, six hundred eighty-three thousand, nine hundred thirty-one".