1917728545 has 8 divisors (see below), whose sum is σ = 2350237824. Its totient is φ = 1501540464.

The previous prime is 1917728543. The next prime is 1917728551. The reversal of 1917728545 is 5458277191.

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

It is a cyclic number.

It is not a de Polignac number, because 1917728545 - 2¹ = 1917728543 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1917728543) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4080039 + ... + 4080508.

It is an arithmetic number, because the mean of its divisors is an integer number (293779728).

Almost surely, 2^1917728545 is an apocalyptic number.

It is an amenable number.

1917728545 is a deficient number, since it is larger than the sum of its proper divisors (432509279).

1917728545 is an equidigital number, since it uses as much as digits as its factorization.

1917728545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8160599.

The product of its digits is 705600, while the sum is 49.

The square root of 1917728545 is about 43791.8776144618. The cubic root of 1917728545 is about 1242.4026743302.

The spelling of 1917728545 in words is "one billion, nine hundred seventeen million, seven hundred twenty-eight thousand, five hundred forty-five".