1671542557 has 4 divisors (see below), whose sum is σ = 1698944956. Its totient is φ = 1644140160.

The previous prime is 1671542531. The next prime is 1671542591. The reversal of 1671542557 is 7552451761.

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 33802596 + 1637739961 = 5814^2 + 40469^2 .

It is a cyclic number.

It is not a de Polignac number, because 1671542557 - 2¹¹ = 1671540509 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1671542057) 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, 13701108 + ... + 13701229.

It is an arithmetic number, because the mean of its divisors is an integer number (424736239).

Almost surely, 2^1671542557 is an apocalyptic number.

It is an amenable number.

1671542557 is a deficient number, since it is larger than the sum of its proper divisors (27402399).

1671542557 is an equidigital number, since it uses as much as digits as its factorization.

1671542557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27402398.

The product of its digits is 294000, while the sum is 43.

The square root of 1671542557 is about 40884.5026507600. The cubic root of 1671542557 is about 1186.7861772687.

The spelling of 1671542557 in words is "one billion, six hundred seventy-one million, five hundred forty-two thousand, five hundred fifty-seven".