21000760 has 48 divisors (see below), whose sum is σ = 51949800. Its totient is φ = 7634880.

The previous prime is 21000739. The next prime is 21000761. The reversal of 21000760 is 6700012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000761) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2671 + ... + 7009.

Almost surely, 2^21000760 is an apocalyptic number.

21000760 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 21000760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25974900).

21000760 is an abundant number, since it is smaller than the sum of its proper divisors (30949040).

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

21000760 is a wasteful number, since it uses less digits than its factorization.

21000760 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4372 (or 4357 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 16.

The square root of 21000760 is about 4582.6586170039. The cubic root of 21000760 is about 275.8957458240.

Adding to 21000760 its reverse (6700012), we get a palindrome (27700772).

The spelling of 21000760 in words is "twenty-one million, seven hundred sixty", and thus it is an aban number.