2121243036651 has 64 divisors (see below), whose sum is σ = 3170691363840. Its totient is φ = 1401589163520.

The previous prime is 2121243036637. The next prime is 2121243036683. The reversal of 2121243036651 is 1566303421212.

2121243036651 is a `hidden beast` number, since 2 + 1 + 2 + 1 + 243 + 0 + 366 + 51 = 666.

It is not a de Polignac number, because 2121243036651 - 2³⁰ = 2120169294827 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2121243036551) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1940752461 + ... + 1940753553.

It is an arithmetic number, because the mean of its divisors is an integer number (49542052560).

Almost surely, 2^{2121243036651} is an apocalyptic number.

2121243036651 is a deficient number, since it is larger than the sum of its proper divisors (1049448327189).

2121243036651 is a wasteful number, since it uses less digits than its factorization.

2121243036651 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2513 (or 2507 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

Adding to 2121243036651 its reverse (1566303421212), we get a palindrome (3687546457863).

The spelling of 2121243036651 in words is "two trillion, one hundred twenty-one billion, two hundred forty-three million, thirty-six thousand, six hundred fifty-one".