1243431377 has 2 divisors, whose sum is σ = 1243431378. Its totient is φ = 1243431376.

The previous prime is 1243431367. The next prime is 1243431407. The reversal of 1243431377 is 7731343421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1126877761 + 116553616 = 33569^2 + 10796^2 .

It is a cyclic number.

It is not a de Polignac number, because 1243431377 - 2¹² = 1243427281 is a prime.

It is a super-2 number, since 2×1243431377² = 3092243178616232258, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1243431337) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621715688 + 621715689.

It is an arithmetic number, because the mean of its divisors is an integer number (621715689).

Almost surely, 2^1243431377 is an apocalyptic number.

It is an amenable number.

1243431377 is a deficient number, since it is larger than the sum of its proper divisors (1).

1243431377 is an equidigital number, since it uses as much as digits as its factorization.

1243431377 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 42336, while the sum is 35.

The square root of 1243431377 is about 35262.3223426932. The cubic root of 1243431377 is about 1075.3271409617.

Adding to 1243431377 its reverse (7731343421), we get a palindrome (8974774798).

The spelling of 1243431377 in words is "one billion, two hundred forty-three million, four hundred thirty-one thousand, three hundred seventy-seven".