2191037988 has 12 divisors (see below), whose sum is σ = 5112422000. Its totient is φ = 730345992.

The previous prime is 2191037977. The next prime is 2191037999. The reversal of 2191037988 is 8897301912.

It is an interprime number because it is at equal distance from previous prime (2191037977) and next prime (2191037999).

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

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 3 ways as a sum of consecutive naturals, for example, 91293238 + ... + 91293261.

Almost surely, 2^2191037988 is an apocalyptic number.

It is an amenable number.

2191037988 is an abundant number, since it is smaller than the sum of its proper divisors (2921384012).

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

2191037988 is a wasteful number, since it uses less digits than its factorization.

2191037988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182586506 (or 182586504 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 48.

The square root of 2191037988 is about 46808.5247364195. The cubic root of 2191037988 is about 1298.8229954251.

The spelling of 2191037988 in words is "two billion, one hundred ninety-one million, thirty-seven thousand, nine hundred eighty-eight".