1261637912747 has 2 divisors, whose sum is σ = 1261637912748. Its totient is φ = 1261637912746.

The previous prime is 1261637912729. The next prime is 1261637912767. The reversal of 1261637912747 is 7472197361621.

It is a weak prime.

It is an emirp because it is prime and its reverse (7472197361621) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1261637912747 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1261637912692 and 1261637912701.

It is not a weakly prime, because it can be changed into another prime (1261637912767) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 630818956373 + 630818956374.

It is an arithmetic number, because the mean of its divisors is an integer number (630818956374).

Almost surely, 2^{1261637912747} is an apocalyptic number.

1261637912747 is a deficient number, since it is larger than the sum of its proper divisors (1).

1261637912747 is an equidigital number, since it uses as much as digits as its factorization.

1261637912747 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5334336, while the sum is 56.

The spelling of 1261637912747 in words is "one trillion, two hundred sixty-one billion, six hundred thirty-seven million, nine hundred twelve thousand, seven hundred forty-seven".