1242649687 has 2 divisors, whose sum is σ = 1242649688. Its totient is φ = 1242649686.

The previous prime is 1242649657. The next prime is 1242649691. The reversal of 1242649687 is 7869462421.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1242649687 - 2⁷ = 1242649559 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1242649687.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1242649627) 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, 621324843 + 621324844.

It is an arithmetic number, because the mean of its divisors is an integer number (621324844).

Almost surely, 2^1242649687 is an apocalyptic number.

1242649687 is a deficient number, since it is larger than the sum of its proper divisors (1).

1242649687 is an equidigital number, since it uses as much as digits as its factorization.

1242649687 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1161216, while the sum is 49.

The square root of 1242649687 is about 35251.2366733424. The cubic root of 1242649687 is about 1075.1017569442.

The spelling of 1242649687 in words is "one billion, two hundred forty-two million, six hundred forty-nine thousand, six hundred eighty-seven".