39820197889 has 4 divisors (see below), whose sum is σ = 40206801856. Its totient is φ = 39433593924.

The previous prime is 39820197871. The next prime is 39820197983. The reversal of 39820197889 is 98879102893.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 39820197889 - 2⁷ = 39820197761 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 39820197889.

It is not an unprimeable number, because it can be changed into a prime (39820197589) 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, 193301829 + ... + 193302034.

It is an arithmetic number, because the mean of its divisors is an integer number (10051700464).

It is a Proth number, since it is equal to 75951 ⋅ 2¹⁹ + 1 and 75951 < 2¹⁹.

Almost surely, 2^39820197889 is an apocalyptic number.

It is an amenable number.

39820197889 is a deficient number, since it is larger than the sum of its proper divisors (386603967).

39820197889 is a wasteful number, since it uses less digits than its factorization.

39820197889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 386603966.

The product of its (nonzero) digits is 15676416, while the sum is 64.

The spelling of 39820197889 in words is "thirty-nine billion, eight hundred twenty million, one hundred ninety-seven thousand, eight hundred eighty-nine".