21000330040 has 32 divisors (see below), whose sum is σ = 47258099280. Its totient is φ = 8398824192.

The previous prime is 21000330017. The next prime is 21000330041. The reversal of 21000330040 is 4003300012.

It is a self number, because there is not a number n which added to its sum of digits gives 21000330040.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000330041) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 243724 + ... + 318436.

Almost surely, 2^21000330040 is an apocalyptic number.

21000330040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21000330040 is an abundant number, since it is smaller than the sum of its proper divisors (26257769240).

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

21000330040 is a wasteful number, since it uses less digits than its factorization.

21000330040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81751 (or 81747 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 13.

Adding to 21000330040 its reverse (4003300012), we get a palindrome (25003630052).

The spelling of 21000330040 in words is "twenty-one billion, three hundred thirty thousand, forty".