1243671137 has 4 divisors (see below), whose sum is σ = 1257645060. Its totient is φ = 1229697216.

The previous prime is 1243671133. The next prime is 1243671161. The reversal of 1243671137 is 7311763421.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 418775296 + 824895841 = 20464^2 + 28721^2 .

It is a cyclic number.

It is not a de Polignac number, because 1243671137 - 2² = 1243671133 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1243671097 and 1243671106.

It is not an unprimeable number, because it can be changed into a prime (1243671133) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6986828 + ... + 6987005.

It is an arithmetic number, because the mean of its divisors is an integer number (314411265).

Almost surely, 2^1243671137 is an apocalyptic number.

It is an amenable number.

1243671137 is a deficient number, since it is larger than the sum of its proper divisors (13973923).

1243671137 is an equidigital number, since it uses as much as digits as its factorization.

1243671137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13973922.

The product of its digits is 21168, while the sum is 35.

The square root of 1243671137 is about 35265.7218414709. The cubic root of 1243671137 is about 1075.3962518299.

The spelling of 1243671137 in words is "one billion, two hundred forty-three million, six hundred seventy-one thousand, one hundred thirty-seven".