1291625623 has 2 divisors, whose sum is σ = 1291625624. Its totient is φ = 1291625622.

The previous prime is 1291625597. The next prime is 1291625663. The reversal of 1291625623 is 3265261921.

It is a weak prime.

It is an emirp because it is prime and its reverse (3265261921) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1291625623 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1291625663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 645812811 + 645812812.

It is an arithmetic number, because the mean of its divisors is an integer number (645812812).

Almost surely, 2^1291625623 is an apocalyptic number.

1291625623 is a deficient number, since it is larger than the sum of its proper divisors (1).

1291625623 is an equidigital number, since it uses as much as digits as its factorization.

1291625623 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 38880, while the sum is 37.

The square root of 1291625623 is about 35939.1934105372. The cubic root of 1291625623 is about 1089.0443108732.

The spelling of 1291625623 in words is "one billion, two hundred ninety-one million, six hundred twenty-five thousand, six hundred twenty-three".