16821840422 has 4 divisors (see below), whose sum is σ = 25232760636. Its totient is φ = 8410920210.

The previous prime is 16821840421. The next prime is 16821840443. The reversal of 16821840422 is 22404812861.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16821840421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4205460104 + ... + 4205460107.

It is an arithmetic number, because the mean of its divisors is an integer number (6308190159).

Almost surely, 2^16821840422 is an apocalyptic number.

16821840422 is a deficient number, since it is larger than the sum of its proper divisors (8410920214).

16821840422 is an equidigital number, since it uses as much as digits as its factorization.

16821840422 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8410920213.

The product of its (nonzero) digits is 49152, while the sum is 38.

The spelling of 16821840422 in words is "sixteen billion, eight hundred twenty-one million, eight hundred forty thousand, four hundred twenty-two".