21011202000 has 120 divisors (see below), whose sum is σ = 73385187720. Its totient is φ = 5602982400.

The previous prime is 21011201987. The next prime is 21011202001. The reversal of 21011202000 is 20211012.

It can be written as a sum of positive squares in 4 ways, for example, as 133263936 + 20877938064 = 11544^2 + 144492^2 .

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21011202001) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 565645 + ... + 601644.

It is an arithmetic number, because the mean of its divisors is an integer number (611543231).

Almost surely, 2^21011202000 is an apocalyptic number.

21011202000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21011202000 is an abundant number, since it is smaller than the sum of its proper divisors (52373985720).

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

21011202000 is a wasteful number, since it uses less digits than its factorization.

21011202000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1167318 (or 1167299 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 21011202000 its reverse (20211012), we get a palindrome (21031413012).

The spelling of 21011202000 in words is "twenty-one billion, eleven million, two hundred two thousand".