1205155129478 has 4 divisors (see below), whose sum is σ = 1807732694220. Its totient is φ = 602577564738.

The previous prime is 1205155129469. The next prime is 1205155129481. The reversal of 1205155129478 is 8749215515021.

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

It is a super-2 number, since 2×1205155129478² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 301288782368 + ... + 301288782371.

It is an arithmetic number, because the mean of its divisors is an integer number (451933173555).

Almost surely, 2^{1205155129478} is an apocalyptic number.

1205155129478 is a deficient number, since it is larger than the sum of its proper divisors (602577564742).

1205155129478 is an equidigital number, since it uses as much as digits as its factorization.

1205155129478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 602577564741.

The product of its (nonzero) digits is 1008000, while the sum is 50.

The spelling of 1205155129478 in words is "one trillion, two hundred five billion, one hundred fifty-five million, one hundred twenty-nine thousand, four hundred seventy-eight".