2100121421 has 16 divisors (see below), whose sum is σ = 2232489600. Its totient is φ = 1971528768.

The previous prime is 2100121409. The next prime is 2100121423. The reversal of 2100121421 is 1241210012.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 2100121421 - 2¹⁰ = 2100120397 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2100121396 and 2100121405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2100121423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 264335 + ... + 272163.

It is an arithmetic number, because the mean of its divisors is an integer number (139530600).

Almost surely, 2^2100121421 is an apocalyptic number.

It is an amenable number.

2100121421 is a deficient number, since it is larger than the sum of its proper divisors (132368179).

2100121421 is a wasteful number, since it uses less digits than its factorization.

2100121421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8068.

The product of its (nonzero) digits is 32, while the sum is 14.

The square root of 2100121421 is about 45827.0817421315. The cubic root of 2100121421 is about 1280.6038453377.

Adding to 2100121421 its reverse (1241210012), we get a palindrome (3341331433).

The spelling of 2100121421 in words is "two billion, one hundred million, one hundred twenty-one thousand, four hundred twenty-one".