1557653990405 has 4 divisors (see below), whose sum is σ = 1869184788492. Its totient is φ = 1246123192320.

The previous prime is 1557653990393. The next prime is 1557653990419. The reversal of 1557653990405 is 5040993567551.

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 832375223716 + 725278766689 = 912346^2 + 851633^2 .

It is not a de Polignac number, because 1557653990405 - 2¹⁸ = 1557653728261 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 155765399036 + ... + 155765399045.

It is an arithmetic number, because the mean of its divisors is an integer number (467296197123).

Almost surely, 2^{1557653990405} is an apocalyptic number.

It is an amenable number.

1557653990405 is a deficient number, since it is larger than the sum of its proper divisors (311530798087).

1557653990405 is an equidigital number, since it uses as much as digits as its factorization.

1557653990405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 311530798086.

The product of its (nonzero) digits is 25515000, while the sum is 59.

The spelling of 1557653990405 in words is "one trillion, five hundred fifty-seven billion, six hundred fifty-three million, nine hundred ninety thousand, four hundred five".