1325572778 has 4 divisors (see below), whose sum is σ = 1988359170. Its totient is φ = 662786388.

The previous prime is 1325572757. The next prime is 1325572789. The reversal of 1325572778 is 8772755231.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 8772755231 = 2297 ⋅3819223.

It can be written as a sum of positive squares in only one way, i.e., 1089858169 + 235714609 = 33013^2 + 15353^2 .

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 331393193 + ... + 331393196.

Almost surely, 2^1325572778 is an apocalyptic number.

1325572778 is a deficient number, since it is larger than the sum of its proper divisors (662786392).

1325572778 is an equidigital number, since it uses as much as digits as its factorization.

1325572778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 662786391.

The product of its digits is 823200, while the sum is 47.

The square root of 1325572778 is about 36408.4163072222. The cubic root of 1325572778 is about 1098.5028607853.

The spelling of 1325572778 in words is "one billion, three hundred twenty-five million, five hundred seventy-two thousand, seven hundred seventy-eight".