1291102621405 has 4 divisors (see below), whose sum is σ = 1549323145692. Its totient is φ = 1032882097120.

The previous prime is 1291102621397. The next prime is 1291102621423. The reversal of 1291102621405 is 5041262011921.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 167377537924 + 1123725083481 = 409118^2 + 1060059^2 .

It is not a de Polignac number, because 1291102621405 - 2³ = 1291102621397 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 129110262136 + ... + 129110262145.

It is an arithmetic number, because the mean of its divisors is an integer number (387330786423).

Almost surely, 2^{1291102621405} is an apocalyptic number.

It is an amenable number.

1291102621405 is a deficient number, since it is larger than the sum of its proper divisors (258220524287).

1291102621405 is an equidigital number, since it uses as much as digits as its factorization.

1291102621405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 258220524286.

The product of its (nonzero) digits is 8640, while the sum is 34.

The spelling of 1291102621405 in words is "one trillion, two hundred ninety-one billion, one hundred two million, six hundred twenty-one thousand, four hundred five".