1990601789 has 16 divisors (see below), whose sum is σ = 2274912000. Its totient is φ = 1725097920.

The previous prime is 1990601777. The next prime is 1990601819. The reversal of 1990601789 is 9871060991.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1990601789 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 (1990201789) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 14294 + ... + 64695.

It is an arithmetic number, because the mean of its divisors is an integer number (142182000).

Almost surely, 2^1990601789 is an apocalyptic number.

It is an amenable number.

1990601789 is a deficient number, since it is larger than the sum of its proper divisors (284310211).

1990601789 is a wasteful number, since it uses less digits than its factorization.

1990601789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79108.

The product of its (nonzero) digits is 244944, while the sum is 50.

The square root of 1990601789 is about 44616.1606259436. The cubic root of 1990601789 is about 1257.9444499252.

The spelling of 1990601789 in words is "one billion, nine hundred ninety million, six hundred one thousand, seven hundred eighty-nine".