1557421543 has 2 divisors, whose sum is σ = 1557421544. Its totient is φ = 1557421542.

The previous prime is 1557421529. The next prime is 1557421577. The reversal of 1557421543 is 3451247551.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1557421543 - 2²¹ = 1555324391 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1557424543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 778710771 + 778710772.

It is an arithmetic number, because the mean of its divisors is an integer number (778710772).

Almost surely, 2^1557421543 is an apocalyptic number.

1557421543 is a deficient number, since it is larger than the sum of its proper divisors (1).

1557421543 is an equidigital number, since it uses as much as digits as its factorization.

1557421543 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 84000, while the sum is 37.

The square root of 1557421543 is about 39464.1805058714. The cubic root of 1557421543 is about 1159.1386647425.

The spelling of 1557421543 in words is "one billion, five hundred fifty-seven million, four hundred twenty-one thousand, five hundred forty-three".