21113103440 has 80 divisors (see below), whose sum is σ = 57669808896. Its totient is φ = 7086912000.

The previous prime is 21113103433. The next prime is 21113103467. The reversal of 21113103440 is 4430131112.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

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, 911336 + ... + 934215.

Almost surely, 2^21113103440 is an apocalyptic number.

21113103440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21113103440 is an abundant number, since it is smaller than the sum of its proper divisors (36556705456).

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

21113103440 is a wasteful number, since it uses less digits than its factorization.

21113103440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1845588 (or 1845582 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 21113103440 its reverse (4430131112), we get a palindrome (25543234552).

The spelling of 21113103440 in words is "twenty-one billion, one hundred thirteen million, one hundred three thousand, four hundred forty".