2191721704 has 32 divisors (see below), whose sum is σ = 4358471040. Its totient is φ = 1031025600.

The previous prime is 2191721699. The next prime is 2191721711. The reversal of 2191721704 is 4071271912.

It is a self number, because there is not a number n which added to its sum of digits gives 2191721704.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 86412 + ... + 108859.

It is an arithmetic number, because the mean of its divisors is an integer number (136202220).

Almost surely, 2^2191721704 is an apocalyptic number.

It is an amenable number.

2191721704 is a deficient number, since it is larger than the sum of its proper divisors (2166749336).

2191721704 is a wasteful number, since it uses less digits than its factorization.

2191721704 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195361 (or 195357 counting only the distinct ones).

The product of its (nonzero) digits is 7056, while the sum is 34.

The square root of 2191721704 is about 46815.8274945557. The cubic root of 2191721704 is about 1298.9580811264.

The spelling of 2191721704 in words is "two billion, one hundred ninety-one million, seven hundred twenty-one thousand, seven hundred four".