21001211122000 has 80 divisors (see below), whose sum is σ = 50782529455632. Its totient is φ = 8400219609600.

The previous prime is 21001211121973. The next prime is 21001211122117. The reversal of 21001211122000 is 22111210012.

It can be written as a sum of positive squares in 8 ways, for example, as 16317172460304 + 4684038661696 = 4039452^2 + 2164264^2 .

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 70918242 + ... + 71213758.

Almost surely, 2^{21001211122000} is an apocalyptic number.

21001211122000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21001211122000 is an abundant number, since it is smaller than the sum of its proper divisors (29781318333632).

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

21001211122000 is a wasteful number, since it uses less digits than its factorization.

21001211122000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 331073 (or 331057 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 21001211122000 its reverse (22111210012), we get a palindrome (21023322332012).

The spelling of 21001211122000 in words is "twenty-one trillion, one billion, two hundred eleven million, one hundred twenty-two thousand".