32161393991 has 4 divisors (see below), whose sum is σ = 32181408912.
Its totient is φ = 32141379072.
The previous prime is 32161393969. The next prime is 32161393997. The reversal of 32161393991 is 19939316123.
It is a happy number.
It is a semiprime because it is the product of two primes.
It is a cyclic number.
It is not a de Polignac number, because 32161393991 - 214 = 32161377607 is a prime.
It is a Duffinian number.
It is a congruent number.
It is not an unprimeable number, because it can be changed into a prime (32161393997) 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, 10005050 + ... + 10008263.
It is an arithmetic number, because the mean of its divisors is an integer number (8045352228).
Almost surely, 232161393991 is an apocalyptic number.
32161393991 is a deficient number, since it is larger than the sum of its proper divisors (20014921).
32161393991 is a wasteful number, since it uses less digits than its factorization.
32161393991 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 20014920.
The product of its digits is 236196, while the sum is 47.
The spelling of 32161393991 in words is "thirty-two billion, one hundred sixty-one million, three hundred ninety-three thousand, nine hundred ninety-one".