1389201985 has 8 divisors (see below), whose sum is σ = 1672370280. Its totient is φ = 1107809664.

The previous prime is 1389201949. The next prime is 1389201991. The reversal of 1389201985 is 5891029831.

It is a Cunningham number, because it is equal to 37272²+1.

It can be written as a sum of positive squares in 4 ways, for example, as 8856576 + 1380345409 = 2976^2 + 37153^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1389201985 - 2¹⁵ = 1389169217 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 442270 + ... + 445399.

It is an arithmetic number, because the mean of its divisors is an integer number (209046285).

Almost surely, 2^1389201985 is an apocalyptic number.

It is an amenable number.

1389201985 is a deficient number, since it is larger than the sum of its proper divisors (283168295).

1389201985 is an equidigital number, since it uses as much as digits as its factorization.

1389201985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 887987.

The product of its (nonzero) digits is 155520, while the sum is 46.

The square root of 1389201985 is about 37272.0000134149. Note that the first 4 decimals coincide. The cubic root of 1389201985 is about 1115.8054159125.

The spelling of 1389201985 in words is "one billion, three hundred eighty-nine million, two hundred one thousand, nine hundred eighty-five".