1350856561 has 4 divisors (see below), whose sum is σ = 1383804324. Its totient is φ = 1317908800.

The previous prime is 1350856553. The next prime is 1350856583. The reversal of 1350856561 is 1656580531.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1656580531 = 19 ⋅87188449.

It can be written as a sum of positive squares in 2 ways, for example, as 821166336 + 529690225 = 28656^2 + 23015^2 .

It is a cyclic number.

It is not a de Polignac number, because 1350856561 - 2³ = 1350856553 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1350856361) 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, 16473820 + ... + 16473901.

It is an arithmetic number, because the mean of its divisors is an integer number (345951081).

Almost surely, 2^1350856561 is an apocalyptic number.

It is an amenable number.

1350856561 is a deficient number, since it is larger than the sum of its proper divisors (32947763).

1350856561 is an equidigital number, since it uses as much as digits as its factorization.

1350856561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32947762.

The product of its (nonzero) digits is 108000, while the sum is 40.

The square root of 1350856561 is about 36754.0006121783. Note that the first 3 decimals coincide. The cubic root of 1350856561 is about 1105.4431481508.

The spelling of 1350856561 in words is "one billion, three hundred fifty million, eight hundred fifty-six thousand, five hundred sixty-one".