2121640644105 has 16 divisors (see below), whose sum is σ = 3771805589760. Its totient is φ = 1131541676784.

The previous prime is 2121640644047. The next prime is 2121640644107. The reversal of 2121640644105 is 5014460461212.

2121640644105 is a `hidden beast` number, since 2 + 1 + 2 + 1 + 6 + 4 + 0 + 644 + 1 + 0 + 5 = 666.

It is not a de Polignac number, because 2121640644105 - 2⁷ = 2121640643977 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2121640644105.

It is not an unprimeable number, because it can be changed into a prime (2121640644107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7857928177 + ... + 7857928446.

It is an arithmetic number, because the mean of its divisors is an integer number (235737849360).

Almost surely, 2^{2121640644105} is an apocalyptic number.

It is an amenable number.

2121640644105 is a deficient number, since it is larger than the sum of its proper divisors (1650164945655).

2121640644105 is a wasteful number, since it uses less digits than its factorization.

2121640644105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15715856637 (or 15715856631 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The spelling of 2121640644105 in words is "two trillion, one hundred twenty-one billion, six hundred forty million, six hundred forty-four thousand, one hundred five".