126711989 has 2 divisors, whose sum is σ = 126711990. Its totient is φ = 126711988.

The previous prime is 126711967. The next prime is 126711997. The reversal of 126711989 is 989117621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 120670225 + 6041764 = 10985^2 + 2458^2 .

It is an emirp because it is prime and its reverse (989117621) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-126711989 is a prime.

It is a super-3 number, since 3×126711989³ (a number of 25 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (126711929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63355994 + 63355995.

It is an arithmetic number, because the mean of its divisors is an integer number (63355995).

Almost surely, 2^126711989 is an apocalyptic number.

It is an amenable number.

126711989 is a deficient number, since it is larger than the sum of its proper divisors (1).

126711989 is an equidigital number, since it uses as much as digits as its factorization.

126711989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54432, while the sum is 44.

The square root of 126711989 is about 11256.6419948402. The cubic root of 126711989 is about 502.2723095746.

The spelling of 126711989 in words is "one hundred twenty-six million, seven hundred eleven thousand, nine hundred eighty-nine".