2921939390868 has 12 divisors (see below), whose sum is σ = 6817858578720. Its totient is φ = 973979796952.

The previous prime is 2921939390857. The next prime is 2921939390869. The reversal of 2921939390868 is 8680939391292.

It is a tau number, because it is divible by the number of its divisors (12).

It is a Smith number, since the sum of its digits (69) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2921939390869) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 121747474608 + ... + 121747474631.

It is an arithmetic number, because the mean of its divisors is an integer number (568154881560).

Almost surely, 2^{2921939390868} is an apocalyptic number.

It is an amenable number.

2921939390868 is an abundant number, since it is smaller than the sum of its proper divisors (3895919187852).

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

2921939390868 is a wasteful number, since it uses less digits than its factorization.

2921939390868 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 243494949246 (or 243494949244 counting only the distinct ones).

The product of its (nonzero) digits is 90699264, while the sum is 69.

The spelling of 2921939390868 in words is "two trillion, nine hundred twenty-one billion, nine hundred thirty-nine million, three hundred ninety thousand, eight hundred sixty-eight".