21744311990 has 48 divisors (see below), whose sum is σ = 39846918384. Its totient is φ = 8543304000.

The previous prime is 21744311957. The next prime is 21744312011. The reversal of 21744311990 is 9911344712.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 31018640 + ... + 31019340.

It is an arithmetic number, because the mean of its divisors is an integer number (830144133).

Almost surely, 2^21744311990 is an apocalyptic number.

21744311990 is a deficient number, since it is larger than the sum of its proper divisors (18102606394).

21744311990 is an equidigital number, since it uses as much as digits as its factorization.

21744311990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1533 (or 1466 counting only the distinct ones).

The product of its (nonzero) digits is 54432, while the sum is 41.

The spelling of 21744311990 in words is "twenty-one billion, seven hundred forty-four million, three hundred eleven thousand, nine hundred ninety".