1605724260557 has 4 divisors (see below), whose sum is σ = 1606799763900. Its totient is φ = 1604648757216.

The previous prime is 1605724260541. The next prime is 1605724260559. The reversal of 1605724260557 is 7550624275061.

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 1418049890761 + 187674369796 = 1190819^2 + 433214^2 .

It is a cyclic number.

It is not a de Polignac number, because 1605724260557 - 2⁴ = 1605724260541 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 (1605724260559) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 537749432 + ... + 537752417.

It is an arithmetic number, because the mean of its divisors is an integer number (401699940975).

Almost surely, 2^{1605724260557} is an apocalyptic number.

It is an amenable number.

1605724260557 is a deficient number, since it is larger than the sum of its proper divisors (1075503343).

1605724260557 is a wasteful number, since it uses less digits than its factorization.

1605724260557 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1075503342.

The product of its (nonzero) digits is 3528000, while the sum is 50.

The spelling of 1605724260557 in words is "one trillion, six hundred five billion, seven hundred twenty-four million, two hundred sixty thousand, five hundred fifty-seven".