1994642865 has 24 divisors (see below), whose sum is σ = 3460722408. Its totient is φ = 1062781440.

The previous prime is 1994642833. The next prime is 1994642873. The reversal of 1994642865 is 5682464991.

It can be written as a sum of positive squares in 4 ways, for example, as 227617569 + 1767025296 = 15087^2 + 42036^2 .

It is not a de Polignac number, because 1994642865 - 2⁵ = 1994642833 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 26857 + ... + 68633.

It is an arithmetic number, because the mean of its divisors is an integer number (144196767).

Almost surely, 2^1994642865 is an apocalyptic number.

1994642865 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1994642865 is a deficient number, since it is larger than the sum of its proper divisors (1466079543).

1994642865 is a wasteful number, since it uses less digits than its factorization.

1994642865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42849 (or 42846 counting only the distinct ones).

The product of its digits is 3732480, while the sum is 54.

The square root of 1994642865 is about 44661.4247981410. The cubic root of 1994642865 is about 1258.7951161402.

The spelling of 1994642865 in words is "one billion, nine hundred ninety-four million, six hundred forty-two thousand, eight hundred sixty-five".