21121210201001 has 16 divisors (see below), whose sum is σ = 21745654554624. Its totient is φ = 20502914189184.

The previous prime is 21121210200971. The next prime is 21121210201009. The reversal of 21121210201001 is 10010201212112.

It is not a de Polignac number, because 21121210201001 - 2³⁴ = 21104030331817 is a prime.

It is a super-2 number, since 2×21121210201001² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21121210201009) 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, 18925400 + ... + 20010326.

It is an arithmetic number, because the mean of its divisors is an integer number (1359103409664).

Almost surely, 2^{21121210201001} is an apocalyptic number.

It is an amenable number.

21121210201001 is a deficient number, since it is larger than the sum of its proper divisors (624444353623).

21121210201001 is a wasteful number, since it uses less digits than its factorization.

21121210201001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1087760.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21121210201001 its reverse (10010201212112), we get a palindrome (31131411413113).

It can be divided in two parts, 211 and 21210201001, that added together give a palindrome (21210201212).

The spelling of 21121210201001 in words is "twenty-one trillion, one hundred twenty-one billion, two hundred ten million, two hundred one thousand, one".