1243646141 has 4 divisors (see below), whose sum is σ = 1251567612. Its totient is φ = 1235724672.

The previous prime is 1243646137. The next prime is 1243646149. The reversal of 1243646141 is 1416463421.

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 314920516 + 928725625 = 17746^2 + 30475^2 .

It is a cyclic number.

It is not a de Polignac number, because 1243646141 - 2² = 1243646137 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1243646098 and 1243646107.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1243646149) 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, 3960500 + ... + 3960813.

It is an arithmetic number, because the mean of its divisors is an integer number (312891903).

Almost surely, 2^1243646141 is an apocalyptic number.

It is an amenable number.

1243646141 is a deficient number, since it is larger than the sum of its proper divisors (7921471).

1243646141 is an equidigital number, since it uses as much as digits as its factorization.

1243646141 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7921470.

The product of its digits is 13824, while the sum is 32.

The square root of 1243646141 is about 35265.3674445624. The cubic root of 1243646141 is about 1075.3890471426.

The spelling of 1243646141 in words is "one billion, two hundred forty-three million, six hundred forty-six thousand, one hundred forty-one".