21011200001 has 6 divisors (see below), whose sum is σ = 23094955506. Its totient is φ = 19101090800.

The previous prime is 21011199991. The next prime is 21011200043. The reversal of 21011200001 is 10000211012.

It can be written as a sum of positive squares in only one way, i.e., 20894991601 + 116208400 = 144551^2 + 10780^2 .

It is not a de Polignac number, because 21011200001 - 2²² = 21007005697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21011200081) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 86823020 + ... + 86823261.

It is an arithmetic number, because the mean of its divisors is an integer number (3849159251).

Almost surely, 2^21011200001 is an apocalyptic number.

It is an amenable number.

21011200001 is a deficient number, since it is larger than the sum of its proper divisors (2083755505).

21011200001 is a wasteful number, since it uses less digits than its factorization.

21011200001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 173646303 (or 173646292 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 21011200001 its reverse (10000211012), we get a palindrome (31011411013).

It can be divided in two parts, 210 and 11200001, that added together give a palindrome (11200211).

The spelling of 21011200001 in words is "twenty-one billion, eleven million, two hundred thousand, one".