1247272189 has 2 divisors, whose sum is σ = 1247272190. Its totient is φ = 1247272188.

The previous prime is 1247272181. The next prime is 1247272199. The reversal of 1247272189 is 9812727421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 852932025 + 394340164 = 29205^2 + 19858^2 .

It is a cyclic number.

It is not a de Polignac number, because 1247272189 - 2³ = 1247272181 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1247272181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 623636094 + 623636095.

It is an arithmetic number, because the mean of its divisors is an integer number (623636095).

Almost surely, 2^1247272189 is an apocalyptic number.

It is an amenable number.

1247272189 is a deficient number, since it is larger than the sum of its proper divisors (1).

1247272189 is an equidigital number, since it uses as much as digits as its factorization.

1247272189 is an evil number, because the sum of its binary digits is even.

The product of its digits is 112896, while the sum is 43.

The square root of 1247272189 is about 35316.7409170212. The cubic root of 1247272189 is about 1076.4331889116.

The spelling of 1247272189 in words is "one billion, two hundred forty-seven million, two hundred seventy-two thousand, one hundred eighty-nine".