1355785985 has 4 divisors (see below), whose sum is σ = 1626943188. Its totient is φ = 1084628784.

The previous prime is 1355785969. The next prime is 1355785999. The reversal of 1355785985 is 5895875531.

It is a happy number.

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 193794241 + 1161991744 = 13921^2 + 34088^2 .

It is a cyclic number.

It is not a de Polignac number, because 1355785985 - 2⁴ = 1355785969 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1355785985.

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, 135578594 + ... + 135578603.

It is an arithmetic number, because the mean of its divisors is an integer number (406735797).

Almost surely, 2^1355785985 is an apocalyptic number.

It is an amenable number.

1355785985 is a deficient number, since it is larger than the sum of its proper divisors (271157203).

1355785985 is an equidigital number, since it uses as much as digits as its factorization.

1355785985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271157202.

The product of its digits is 7560000, while the sum is 56.

The square root of 1355785985 is about 36820.9992395644. Note that the first 3 decimals coincide. The cubic root of 1355785985 is about 1106.7861437251.

Adding to 1355785985 its sum of digits (56), we get a square (1355786041 = 36821²).

The spelling of 1355785985 in words is "one billion, three hundred fifty-five million, seven hundred eighty-five thousand, nine hundred eighty-five".