21234000040 has 128 divisors (see below), whose sum is σ = 53531694720. Its totient is φ = 7513292800.

The previous prime is 21234000023. The next prime is 21234000089. The reversal of 21234000040 is 4000043212.

It is a junction number, because it is equal to n+sod(n) for n = 21233999978 and 21234000023.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7990392 + ... + 7993048.

It is an arithmetic number, because the mean of its divisors is an integer number (418216365).

Almost surely, 2^21234000040 is an apocalyptic number.

21234000040 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 21234000040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26765847360).

21234000040 is an abundant number, since it is smaller than the sum of its proper divisors (32297694680).

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

21234000040 is a wasteful number, since it uses less digits than its factorization.

21234000040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3163 (or 3159 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 16.

Adding to 21234000040 its reverse (4000043212), we get a palindrome (25234043252).

The spelling of 21234000040 in words is "twenty-one billion, two hundred thirty-four million, forty", and thus it is an aban number.