1540505543 has 4 divisors (see below), whose sum is σ = 1540864920. Its totient is φ = 1540146168.

The previous prime is 1540505497. The next prime is 1540505557. The reversal of 1540505543 is 3455050451.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3455050451 = 4373 ⋅790087.

It is a cyclic number.

It is not a de Polignac number, because 1540505543 - 2⁸ = 1540505287 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 (1540505443) 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, 173180 + ... + 181857.

It is an arithmetic number, because the mean of its divisors is an integer number (385216230).

Almost surely, 2^1540505543 is an apocalyptic number.

1540505543 is a deficient number, since it is larger than the sum of its proper divisors (359377).

1540505543 is an equidigital number, since it uses as much as digits as its factorization.

1540505543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 359376.

The product of its (nonzero) digits is 30000, while the sum is 32.

The square root of 1540505543 is about 39249.2744264146. The cubic root of 1540505543 is about 1154.9267003701.

Adding to 1540505543 its reverse (3455050451), we get a palindrome (4995555994).

The spelling of 1540505543 in words is "one billion, five hundred forty million, five hundred five thousand, five hundred forty-three".