21010990000 has 400 divisors, whose sum is σ = 68333126400. Its totient is φ = 6042240000.

The previous prime is 21010989997. The next prime is 21010990009. The reversal of 21010990000 is 9901012.

It is a tau number, because it is divible by the number of its divisors (400).

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21010990009) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 10008951 + ... + 10011049.

It is an arithmetic number, because the mean of its divisors is an integer number (170832816).

Almost surely, 2^21010990000 is an apocalyptic number.

21010990000 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 21010990000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34166563200).

21010990000 is an abundant number, since it is smaller than the sum of its proper divisors (47322136400).

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

21010990000 is a wasteful number, since it uses less digits than its factorization.

21010990000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2158 (or 2137 counting only the distinct ones).

The product of its (nonzero) digits is 162, while the sum is 22.

The spelling of 21010990000 in words is "twenty-one billion, ten million, nine hundred ninety thousand".