2121721205102 has 4 divisors (see below), whose sum is σ = 3182581807656. Its totient is φ = 1060860602550.

The previous prime is 2121721205099. The next prime is 2121721205111. The reversal of 2121721205102 is 2015021271212.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 530430301274 + ... + 530430301277.

It is an arithmetic number, because the mean of its divisors is an integer number (795645451914).

Almost surely, 2^{2121721205102} is an apocalyptic number.

2121721205102 is a deficient number, since it is larger than the sum of its proper divisors (1060860602554).

2121721205102 is a wasteful number, since it uses less digits than its factorization.

2121721205102 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1060860602553.

The product of its (nonzero) digits is 1120, while the sum is 26.

Adding to 2121721205102 its reverse (2015021271212), we get a palindrome (4136742476314).

The spelling of 2121721205102 in words is "two trillion, one hundred twenty-one billion, seven hundred twenty-one million, two hundred five thousand, one hundred two".