6907747909921 has 4 divisors (see below), whose sum is σ = 6907789613844. Its totient is φ = 6907706206000.

The previous prime is 6907747909903. The next prime is 6907747909957. The reversal of 6907747909921 is 1299097477096.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3954629390625 + 2953118519296 = 1988625^2 + 1718464^2 .

It is a cyclic number.

It is not a de Polignac number, because 6907747909921 - 2¹⁹ = 6907747385633 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6907747909961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20602510 + ... + 20935111.

It is an arithmetic number, because the mean of its divisors is an integer number (1726947403461).

Almost surely, 2^{6907747909921} is an apocalyptic number.

It is an amenable number.

6907747909921 is a deficient number, since it is larger than the sum of its proper divisors (41703923).

6907747909921 is a wasteful number, since it uses less digits than its factorization.

6907747909921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41703922.

The product of its (nonzero) digits is 108020304, while the sum is 70.

The spelling of 6907747909921 in words is "six trillion, nine hundred seven billion, seven hundred forty-seven million, nine hundred nine thousand, nine hundred twenty-one".