21743450787 has 4 divisors (see below), whose sum is σ = 28991267720. Its totient is φ = 14495633856.

The previous prime is 21743450783. The next prime is 21743450803. The reversal of 21743450787 is 78705434712.

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

It is not a de Polignac number, because 21743450787 - 2² = 21743450783 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21743450783) 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, 3623908462 + ... + 3623908467.

It is an arithmetic number, because the mean of its divisors is an integer number (7247816930).

Almost surely, 2^21743450787 is an apocalyptic number.

21743450787 is a deficient number, since it is larger than the sum of its proper divisors (7247816933).

21743450787 is an equidigital number, since it uses as much as digits as its factorization.

21743450787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7247816932.

The product of its (nonzero) digits is 1317120, while the sum is 48.

The spelling of 21743450787 in words is "twenty-one billion, seven hundred forty-three million, four hundred fifty thousand, seven hundred eighty-seven".