1240430557 has 2 divisors, whose sum is σ = 1240430558. Its totient is φ = 1240430556.

The previous prime is 1240430537. The next prime is 1240430593. The reversal of 1240430557 is 7550340421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1164583876 + 75846681 = 34126^2 + 8709^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1240430557 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1240430507) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 620215278 + 620215279.

It is an arithmetic number, because the mean of its divisors is an integer number (620215279).

Almost surely, 2^1240430557 is an apocalyptic number.

It is an amenable number.

1240430557 is a deficient number, since it is larger than the sum of its proper divisors (1).

1240430557 is an equidigital number, since it uses as much as digits as its factorization.

1240430557 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16800, while the sum is 31.

The square root of 1240430557 is about 35219.7466913094. The cubic root of 1240430557 is about 1074.4614015855.

Adding to 1240430557 its reverse (7550340421), we get a palindrome (8790770978).

The spelling of 1240430557 in words is "one billion, two hundred forty million, four hundred thirty thousand, five hundred fifty-seven".