9990889877 has 2 divisors, whose sum is σ = 9990889878. Its totient is φ = 9990889876.

The previous prime is 9990889849. The next prime is 9990889933. The reversal of 9990889877 is 7789880999.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 9950262001 + 40627876 = 99751^2 + 6374^2 .

It is an emirp because it is prime and its reverse (7789880999) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 9990889877 - 2¹⁸ = 9990627733 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9990889177) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4995444938 + 4995444939.

It is an arithmetic number, because the mean of its divisors is an integer number (4995444939).

Almost surely, 2^9990889877 is an apocalyptic number.

It is an amenable number.

9990889877 is a deficient number, since it is larger than the sum of its proper divisors (1).

9990889877 is an equidigital number, since it uses as much as digits as its factorization.

9990889877 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 164602368, while the sum is 74.

The square root of 9990889877 is about 99954.4390059791. The cubic root of 9990889877 is about 2153.7802524240.

The spelling of 9990889877 in words is "nine billion, nine hundred ninety million, eight hundred eighty-nine thousand, eight hundred seventy-seven".