1281658402639 has 2 divisors, whose sum is σ = 1281658402640. Its totient is φ = 1281658402638.

The previous prime is 1281658402589. The next prime is 1281658402649. The reversal of 1281658402639 is 9362048561821.

It is a strong prime.

It is an emirp because it is prime and its reverse (9362048561821) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1281658402639 - 2⁹ = 1281658402127 is a prime.

It is a super-2 number, since 2×1281658402639² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1281658402639.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1281658402649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 640829201319 + 640829201320.

It is an arithmetic number, because the mean of its divisors is an integer number (640829201320).

Almost surely, 2^{1281658402639} is an apocalyptic number.

1281658402639 is a deficient number, since it is larger than the sum of its proper divisors (1).

1281658402639 is an equidigital number, since it uses as much as digits as its factorization.

1281658402639 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4976640, while the sum is 55.

The spelling of 1281658402639 in words is "one trillion, two hundred eighty-one billion, six hundred fifty-eight million, four hundred two thousand, six hundred thirty-nine".