2121011021121 has 4 divisors (see below), whose sum is σ = 2828014694832. Its totient is φ = 1414007347412.

The previous prime is 2121011021113. The next prime is 2121011021137. The reversal of 2121011021121 is 1211201101212.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2121011021121 - 2³ = 2121011021113 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2121011021121.

It is not an unprimeable number, because it can be changed into a prime (2121011021021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 353501836851 + ... + 353501836856.

It is an arithmetic number, because the mean of its divisors is an integer number (707003673708).

Almost surely, 2^{2121011021121} is an apocalyptic number.

It is an amenable number.

2121011021121 is a deficient number, since it is larger than the sum of its proper divisors (707003673711).

2121011021121 is an equidigital number, since it uses as much as digits as its factorization.

2121011021121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 707003673710.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 2121011021121 its reverse (1211201101212), we get a palindrome (3332212122333).

The spelling of 2121011021121 in words is "two trillion, one hundred twenty-one billion, eleven million, twenty-one thousand, one hundred twenty-one".