1990659893 has 2 divisors, whose sum is σ = 1990659894. Its totient is φ = 1990659892.

The previous prime is 1990659883. The next prime is 1990659907. The reversal of 1990659893 is 3989560991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1420309969 + 570349924 = 37687^2 + 23882^2 .

It is a cyclic number.

It is not a de Polignac number, because 1990659893 - 2¹⁰ = 1990658869 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1990659883) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 995329946 + 995329947.

It is an arithmetic number, because the mean of its divisors is an integer number (995329947).

Almost surely, 2^1990659893 is an apocalyptic number.

It is an amenable number.

1990659893 is a deficient number, since it is larger than the sum of its proper divisors (1).

1990659893 is an equidigital number, since it uses as much as digits as its factorization.

1990659893 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4723920, while the sum is 59.

The square root of 1990659893 is about 44616.8117753835. The cubic root of 1990659893 is about 1257.9566892546.

The spelling of 1990659893 in words is "one billion, nine hundred ninety million, six hundred fifty-nine thousand, eight hundred ninety-three".