21040145043 has 4 divisors (see below), whose sum is σ = 28053526728. Its totient is φ = 14026763360.

The previous prime is 21040145011. The next prime is 21040145051. The reversal of 21040145043 is 34054104012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21040145043 - 2⁵ = 21040145011 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21040144043) 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, 3506690838 + ... + 3506690843.

It is an arithmetic number, because the mean of its divisors is an integer number (7013381682).

Almost surely, 2^21040145043 is an apocalyptic number.

21040145043 is a deficient number, since it is larger than the sum of its proper divisors (7013381685).

21040145043 is an equidigital number, since it uses as much as digits as its factorization.

21040145043 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7013381684.

The product of its (nonzero) digits is 1920, while the sum is 24.

Adding to 21040145043 its reverse (34054104012), we get a palindrome (55094249055).

The spelling of 21040145043 in words is "twenty-one billion, forty million, one hundred forty-five thousand, forty-three".