21103409340 has 576 divisors, whose sum is σ = 76523166720. Its totient is φ = 4658135040.

The previous prime is 21103409339. The next prime is 21103409377. The reversal of 21103409340 is 4390430112.

21103409340 is a `hidden beast` number, since 211 + 0 + 3 + 409 + 3 + 40 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 134416542 + ... + 134416698.

It is an arithmetic number, because the mean of its divisors is an integer number (132852720).

Almost surely, 2^21103409340 is an apocalyptic number.

21103409340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21103409340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38261583360).

21103409340 is an abundant number, since it is smaller than the sum of its proper divisors (55419757380).

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

21103409340 is a wasteful number, since it uses less digits than its factorization.

21103409340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 342 (or 337 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

Adding to 21103409340 its reverse (4390430112), we get a palindrome (25493839452).

The spelling of 21103409340 in words is "twenty-one billion, one hundred three million, four hundred nine thousand, three hundred forty".