210121220001 has 96 divisors (see below), whose sum is σ = 380540215296. Its totient is φ = 100071936000.

The previous prime is 210121219969. The next prime is 210121220027. The reversal of 210121220001 is 100022121012.

It is not a de Polignac number, because 210121220001 - 2⁵ = 210121219969 is a prime.

It is not an unprimeable number, because it can be changed into a prime (210121220051) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 2544481 + ... + 2625761.

It is an arithmetic number, because the mean of its divisors is an integer number (3963960576).

Almost surely, 2^210121220001 is an apocalyptic number.

210121220001 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

210121220001 is a deficient number, since it is larger than the sum of its proper divisors (170418995295).

210121220001 is a wasteful number, since it uses less digits than its factorization.

210121220001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81371 (or 81352 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 210121220001 its reverse (100022121012), we get a palindrome (310143341013).

The spelling of 210121220001 in words is "two hundred ten billion, one hundred twenty-one million, two hundred twenty thousand, one".