16640540243 has 2 divisors, whose sum is σ = 16640540244. Its totient is φ = 16640540242.

The previous prime is 16640540237. The next prime is 16640540281. The reversal of 16640540243 is 34204504661.

It is a weak prime.

It is an emirp because it is prime and its reverse (34204504661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16640540243 - 2⁸ = 16640539987 is a prime.

It is not a weakly prime, because it can be changed into another prime (16640540143) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8320270121 + 8320270122.

It is an arithmetic number, because the mean of its divisors is an integer number (8320270122).

Almost surely, 2^16640540243 is an apocalyptic number.

16640540243 is a deficient number, since it is larger than the sum of its proper divisors (1).

16640540243 is an equidigital number, since it uses as much as digits as its factorization.

16640540243 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 69120, while the sum is 35.

The spelling of 16640540243 in words is "sixteen billion, six hundred forty million, five hundred forty thousand, two hundred forty-three".