21021120212001 has 16 divisors (see below), whose sum is σ = 34496197271424. Its totient is φ = 11088063408384.

The previous prime is 21021120211967. The next prime is 21021120212021. The reversal of 21021120212001 is 10021202112012.

It is not a de Polignac number, because 21021120212001 - 2⁹ = 21021120211489 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21021120212021) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38500219896 + ... + 38500220441.

It is an arithmetic number, because the mean of its divisors is an integer number (2156012329464).

Almost surely, 2^{21021120212001} is an apocalyptic number.

21021120212001 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21021120212001 is a deficient number, since it is larger than the sum of its proper divisors (13475077059423).

21021120212001 is a wasteful number, since it uses less digits than its factorization.

21021120212001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77000440360.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21021120212001 its reverse (10021202112012), we get a palindrome (31042322324013).

The spelling of 21021120212001 in words is "twenty-one trillion, twenty-one billion, one hundred twenty million, two hundred twelve thousand, one".