21004433340 has 96 divisors (see below), whose sum is σ = 64183795200. Its totient is φ = 5090016000.

The previous prime is 21004433297. The next prime is 21004433357. The reversal of 21004433340 is 4333440012.

It is a self number, because there is not a number n which added to its sum of digits gives 21004433340.

It is a congruent number.

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, 2438361 + ... + 2446959.

It is an arithmetic number, because the mean of its divisors is an integer number (668581200).

Almost surely, 2^21004433340 is an apocalyptic number.

21004433340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21004433340 is an abundant number, since it is smaller than the sum of its proper divisors (43179361860).

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

21004433340 is a wasteful number, since it uses less digits than its factorization.

21004433340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12323 (or 12321 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 24.

Adding to 21004433340 its reverse (4333440012), we get a palindrome (25337873352).

The spelling of 21004433340 in words is "twenty-one billion, four million, four hundred thirty-three thousand, three hundred forty".