21231735040 has 144 divisors (see below), whose sum is σ = 52531617600. Its totient is φ = 8216764416.

The previous prime is 21231734963. The next prime is 21231735043. The reversal of 21231735040 is 4053713212.

It is not an unprimeable number, because it can be changed into a prime (21231735043) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5997591 + ... + 6001129.

It is an arithmetic number, because the mean of its divisors is an integer number (364802900).

Almost surely, 2^21231735040 is an apocalyptic number.

21231735040 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 21231735040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26265808800).

21231735040 is an abundant number, since it is smaller than the sum of its proper divisors (31299882560).

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

21231735040 is a wasteful number, since it uses less digits than its factorization.

21231735040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3712 (or 3698 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 28.

The spelling of 21231735040 in words is "twenty-one billion, two hundred thirty-one million, seven hundred thirty-five thousand, forty".