21030024440 has 64 divisors (see below), whose sum is σ = 47696117760. Its totient is φ = 8344958080.

The previous prime is 21030024419. The next prime is 21030024451. The reversal of 21030024440 is 4442003012.

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, 2922527 + ... + 2929713.

It is an arithmetic number, because the mean of its divisors is an integer number (745251840).

Almost surely, 2^21030024440 is an apocalyptic number.

21030024440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21030024440 is an abundant number, since it is smaller than the sum of its proper divisors (26666093320).

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

21030024440 is a wasteful number, since it uses less digits than its factorization.

21030024440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7772 (or 7768 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 20.

Adding to 21030024440 its reverse (4442003012), we get a palindrome (25472027452).

The spelling of 21030024440 in words is "twenty-one billion, thirty million, twenty-four thousand, four hundred forty".