21403040343 has 4 divisors (see below), whose sum is σ = 28537387128. Its totient is φ = 14268693560.

The previous prime is 21403040299. The next prime is 21403040363. The reversal of 21403040343 is 34304030412.

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 21403040343 - 2¹⁰ = 21403039319 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21403040363) 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, 3567173388 + ... + 3567173393.

It is an arithmetic number, because the mean of its divisors is an integer number (7134346782).

Almost surely, 2^21403040343 is an apocalyptic number.

21403040343 is a deficient number, since it is larger than the sum of its proper divisors (7134346785).

21403040343 is an equidigital number, since it uses as much as digits as its factorization.

21403040343 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7134346784.

The product of its (nonzero) digits is 3456, while the sum is 24.

Adding to 21403040343 its reverse (34304030412), we get a palindrome (55707070755).

The spelling of 21403040343 in words is "twenty-one billion, four hundred three million, forty thousand, three hundred forty-three".