1239791985 has 12 divisors (see below), whose sum is σ = 2148972852. Its totient is φ = 661222368.

The previous prime is 1239791941. The next prime is 1239792007. The reversal of 1239791985 is 5891979321.

It can be written as a sum of positive squares in 2 ways, for example, as 142062561 + 1097729424 = 11919^2 + 33132^2 .

It is not a de Polignac number, because 1239791985 - 2¹¹ = 1239789937 is a prime.

It is a super-3 number, since 3×1239791985³ (a number of 28 digits) contains 333 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13775422 + ... + 13775511.

It is an arithmetic number, because the mean of its divisors is an integer number (179081071).

Almost surely, 2^1239791985 is an apocalyptic number.

1239791985 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1239791985 is a deficient number, since it is larger than the sum of its proper divisors (909180867).

1239791985 is a wasteful number, since it uses less digits than its factorization.

1239791985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27550944 (or 27550941 counting only the distinct ones).

The product of its digits is 1224720, while the sum is 54.

The square root of 1239791985 is about 35210.6799849137. The cubic root of 1239791985 is about 1074.2769928375.

The spelling of 1239791985 in words is "one billion, two hundred thirty-nine million, seven hundred ninety-one thousand, nine hundred eighty-five".