21344304440 has 32 divisors (see below), whose sum is σ = 50849668080. Its totient is φ = 8035502592.

The previous prime is 21344304391. The next prime is 21344304461. The reversal of 21344304440 is 4440344312.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15693662 + ... + 15695021.

Almost surely, 2^21344304440 is an apocalyptic number.

21344304440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21344304440 is an abundant number, since it is smaller than the sum of its proper divisors (29505363640).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21344304440 is a wasteful number, since it uses less digits than its factorization.

21344304440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31388711 (or 31388707 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 29.

Adding to 21344304440 its reverse (4440344312), we get a palindrome (25784648752).

The spelling of 21344304440 in words is "twenty-one billion, three hundred forty-four million, three hundred four thousand, four hundred forty".