1331111989 has 2 divisors, whose sum is σ = 1331111990. Its totient is φ = 1331111988.

The previous prime is 1331111939. The next prime is 1331112017. The reversal of 1331111989 is 9891111331.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1027202500 + 303909489 = 32050^2 + 17433^2 .

It is an emirp because it is prime and its reverse (9891111331) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1331111989 - 2²¹ = 1329014837 is a prime.

It is a super-2 number, since 2×1331111989² = 3543718254519072242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1331111939) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 665555994 + 665555995.

It is an arithmetic number, because the mean of its divisors is an integer number (665555995).

Almost surely, 2^1331111989 is an apocalyptic number.

It is an amenable number.

1331111989 is a deficient number, since it is larger than the sum of its proper divisors (1).

1331111989 is an equidigital number, since it uses as much as digits as its factorization.

1331111989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5832, while the sum is 37.

The square root of 1331111989 is about 36484.4074777157. The cubic root of 1331111989 is about 1100.0308500990.

The spelling of 1331111989 in words is "one billion, three hundred thirty-one million, one hundred eleven thousand, nine hundred eighty-nine".