21110353440 has 96 divisors (see below), whose sum is σ = 72542869056. Its totient is φ = 5117660160.

The previous prime is 21110353417. The next prime is 21110353457. The reversal of 21110353440 is 4435301112.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 21110353440.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1993807 + ... + 2004366.

It is an arithmetic number, because the mean of its divisors is an integer number (755654886).

Almost surely, 2^21110353440 is an apocalyptic number.

21110353440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21110353440 is an abundant number, since it is smaller than the sum of its proper divisors (51432515616).

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

21110353440 is a wasteful number, since it uses less digits than its factorization.

21110353440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3998202 (or 3998194 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 24.

Adding to 21110353440 its reverse (4435301112), we get a palindrome (25545654552).

The spelling of 21110353440 in words is "twenty-one billion, one hundred ten million, three hundred fifty-three thousand, four hundred forty".