1921040543 has 4 divisors (see below), whose sum is σ = 2022147960. Its totient is φ = 1819933128.

The previous prime is 1921040453. The next prime is 1921040557. The reversal of 1921040543 is 3450401291.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3450401291 = 1103 ⋅3128197.

It is a cyclic number.

It is not a de Polignac number, because 1921040543 - 2⁸ = 1921040287 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1921040593) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 50553680 + ... + 50553717.

It is an arithmetic number, because the mean of its divisors is an integer number (505536990).

Almost surely, 2^1921040543 is an apocalyptic number.

1921040543 is a deficient number, since it is larger than the sum of its proper divisors (101107417).

1921040543 is a wasteful number, since it uses less digits than its factorization.

1921040543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101107416.

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 1921040543 is about 43829.6765103280. The cubic root of 1921040543 is about 1243.1174902378.

The spelling of 1921040543 in words is "one billion, nine hundred twenty-one million, forty thousand, five hundred forty-three".