557406746921 has 4 divisors (see below), whose sum is σ = 557408299344. Its totient is φ = 557405194500.

The previous prime is 557406746899. The next prime is 557406746959. The reversal of 557406746921 is 129647604755.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-557406746921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (557406046921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69566 + ... + 1058136.

It is an arithmetic number, because the mean of its divisors is an integer number (139352074836).

Almost surely, 2^557406746921 is an apocalyptic number.

It is an amenable number.

557406746921 is a deficient number, since it is larger than the sum of its proper divisors (1552423).

557406746921 is an equidigital number, since it uses as much as digits as its factorization.

557406746921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1552422.

The product of its (nonzero) digits is 12700800, while the sum is 56.

The spelling of 557406746921 in words is "five hundred fifty-seven billion, four hundred six million, seven hundred forty-six thousand, nine hundred twenty-one".