1278204131 has 4 divisors (see below), whose sum is σ = 1290150072. Its totient is φ = 1266258192.

The previous prime is 1278204113. The next prime is 1278204163. The reversal of 1278204131 is 1314028721.

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

It is a cyclic number.

It is not a de Polignac number, because 1278204131 - 2¹⁴ = 1278187747 is a prime.

It is a super-2 number, since 2×1278204131² = 3267611601010930322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1278204094 and 1278204103.

It is not an unprimeable number, because it can be changed into a prime (1278204181) 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 in 3 ways as a sum of consecutive naturals, for example, 5972810 + ... + 5973023.

It is an arithmetic number, because the mean of its divisors is an integer number (322537518).

Almost surely, 2^1278204131 is an apocalyptic number.

1278204131 is a deficient number, since it is larger than the sum of its proper divisors (11945941).

1278204131 is a wasteful number, since it uses less digits than its factorization.

1278204131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11945940.

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 1278204131 is about 35751.9807982719. The cubic root of 1278204131 is about 1085.2590237193.

The spelling of 1278204131 in words is "one billion, two hundred seventy-eight million, two hundred four thousand, one hundred thirty-one".