39220981991 has 4 divisors (see below), whose sum is σ = 39222909912. Its totient is φ = 39219054072.

The previous prime is 39220981973. The next prime is 39220982027. The reversal of 39220981991 is 19918902293.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-39220981991 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 (39220986991) 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, 933116 + ... + 974241.

It is an arithmetic number, because the mean of its divisors is an integer number (9805727478).

Almost surely, 2^39220981991 is an apocalyptic number.

39220981991 is a deficient number, since it is larger than the sum of its proper divisors (1927921).

39220981991 is a wasteful number, since it uses less digits than its factorization.

39220981991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1927920.

The product of its (nonzero) digits is 629856, while the sum is 53.

The spelling of 39220981991 in words is "thirty-nine billion, two hundred twenty million, nine hundred eighty-one thousand, nine hundred ninety-one".