2121670181749 has 16 divisors (see below), whose sum is σ = 2236690195200. Its totient is φ = 2006986830336.

The previous prime is 2121670181737. The next prime is 2121670181753. The reversal of 2121670181749 is 9471810761212.

It is a cyclic number.

It is not a de Polignac number, because 2121670181749 - 2⁷ = 2121670181621 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121670181759) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 65664132 + ... + 65696434.

It is an arithmetic number, because the mean of its divisors is an integer number (139793137200).

Almost surely, 2^{2121670181749} is an apocalyptic number.

It is an amenable number.

2121670181749 is a deficient number, since it is larger than the sum of its proper divisors (115020013451).

2121670181749 is a wasteful number, since it uses less digits than its factorization.

2121670181749 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37404.

The product of its (nonzero) digits is 338688, while the sum is 49.

The spelling of 2121670181749 in words is "two trillion, one hundred twenty-one billion, six hundred seventy million, one hundred eighty-one thousand, seven hundred forty-nine".