21000011201001 has 12 divisors (see below), whose sum is σ = 34666685157312. Its totient is φ = 12000006400536.

The previous prime is 21000011200963. The next prime is 21000011201009. The reversal of 21000011201001 is 10010211000012.

It is a happy number.

It is not a de Polignac number, because 21000011201001 - 2⁷ = 21000011200873 is a prime.

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

It is not an unprimeable number, because it can be changed into a prime (21000011201009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 166666755501 + ... + 166666755626.

It is an arithmetic number, because the mean of its divisors is an integer number (2888890429776).

Almost surely, 2^{21000011201001} is an apocalyptic number.

21000011201001 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21000011201001 is a deficient number, since it is larger than the sum of its proper divisors (13666673956311).

21000011201001 is a wasteful number, since it uses less digits than its factorization.

21000011201001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333333511140 (or 333333511137 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 21000011201001 its reverse (10010211000012), we get a palindrome (31010222201013).

The spelling of 21000011201001 in words is "twenty-one trillion, eleven million, two hundred one thousand, one".