1989695233 has 2 divisors, whose sum is σ = 1989695234. Its totient is φ = 1989695232.

The previous prime is 1989695231. The next prime is 1989695237. The reversal of 1989695233 is 3325969891.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1816720129 + 172975104 = 42623^2 + 13152^2 .

It is a cyclic number.

It is not a de Polignac number, because 1989695233 - 2¹ = 1989695231 is a prime.

Together with 1989695231, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1989695231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 994847616 + 994847617.

It is an arithmetic number, because the mean of its divisors is an integer number (994847617).

Almost surely, 2^1989695233 is an apocalyptic number.

It is an amenable number.

1989695233 is a deficient number, since it is larger than the sum of its proper divisors (1).

1989695233 is an equidigital number, since it uses as much as digits as its factorization.

1989695233 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3149280, while the sum is 55.

The square root of 1989695233 is about 44605.9999663722. Note that the first 4 decimals coincide. The cubic root of 1989695233 is about 1257.7534573892.

The spelling of 1989695233 in words is "one billion, nine hundred eighty-nine million, six hundred ninety-five thousand, two hundred thirty-three".