1351783778 has 8 divisors (see below), whose sum is σ = 2055452268. Its totient is φ = 666633024.

The previous prime is 1351783777. The next prime is 1351783787. The reversal of 1351783778 is 8773871531.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1310657209 + 41126569 = 36203^2 + 6413^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (1351783777) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4629251 + ... + 4629542.

Almost surely, 2^1351783778 is an apocalyptic number.

1351783778 is a deficient number, since it is larger than the sum of its proper divisors (703668490).

1351783778 is an equidigital number, since it uses as much as digits as its factorization.

1351783778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9258868.

The product of its digits is 987840, while the sum is 50.

The square root of 1351783778 is about 36766.6122725497. The cubic root of 1351783778 is about 1105.6960127120.

The spelling of 1351783778 in words is "one billion, three hundred fifty-one million, seven hundred eighty-three thousand, seven hundred seventy-eight".