1011665989 has 2 divisors, whose sum is σ = 1011665990. Its totient is φ = 1011665988.

The previous prime is 1011665987. The next prime is 1011666011. The reversal of 1011665989 is 9895661101.

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., 934524900 + 77141089 = 30570^2 + 8783^2 .

It is a cyclic number.

It is not a de Polignac number, because 1011665989 - 2¹ = 1011665987 is a prime.

Together with 1011665987, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1011665987) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 505832994 + 505832995.

It is an arithmetic number, because the mean of its divisors is an integer number (505832995).

Almost surely, 2^1011665989 is an apocalyptic number.

It is an amenable number.

1011665989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1011665989 is an equidigital number, since it uses as much as digits as its factorization.

1011665989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 116640, while the sum is 46.

The square root of 1011665989 is about 31806.6972350164. The cubic root of 1011665989 is about 1003.8736385496.

The spelling of 1011665989 in words is "one billion, eleven million, six hundred sixty-five thousand, nine hundred eighty-nine".