2171944993 has 16 divisors (see below), whose sum is σ = 2317011840. Its totient is φ = 2031473664.

The previous prime is 2171944991. The next prime is 2171945047. The reversal of 2171944993 is 3994491712.

It is a cyclic number.

It is not a de Polignac number, because 2171944993 - 2¹ = 2171944991 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2171944991) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 257755 + ... + 266047.

It is an arithmetic number, because the mean of its divisors is an integer number (144813240).

Almost surely, 2^2171944993 is an apocalyptic number.

2171944993 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

2171944993 is a deficient number, since it is larger than the sum of its proper divisors (145066847).

2171944993 is a wasteful number, since it uses less digits than its factorization.

2171944993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8568.

The product of its digits is 489888, while the sum is 49.

The square root of 2171944993 is about 46604.1306431093. The cubic root of 2171944993 is about 1295.0392782867.

The spelling of 2171944993 in words is "two billion, one hundred seventy-one million, nine hundred forty-four thousand, nine hundred ninety-three".