2121681189408 has 96 divisors (see below), whose sum is σ = 6166406050560. Its totient is φ = 633337647360.

The previous prime is 2121681189403. The next prime is 2121681189409. The reversal of 2121681189408 is 8049811861212.

It is a tau number, because it is divible by the number of its divisors (96).

It is not an unprimeable number, because it can be changed into a prime (2121681189403) 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, 14923038 + ... + 15064541.

It is an arithmetic number, because the mean of its divisors is an integer number (64233396360).

Almost surely, 2^{2121681189408} is an apocalyptic number.

It is an amenable number.

2121681189408 is an abundant number, since it is smaller than the sum of its proper divisors (4044724861152).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

2121681189408 is a wasteful number, since it uses less digits than its factorization.

2121681189408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29987670 (or 29987662 counting only the distinct ones).

The product of its (nonzero) digits is 442368, while the sum is 51.

The spelling of 2121681189408 in words is "two trillion, one hundred twenty-one billion, six hundred eighty-one million, one hundred eighty-nine thousand, four hundred eight".