1618605665 has 8 divisors (see below), whose sum is σ = 1946384640. Its totient is φ = 1292179312.

The previous prime is 1618605661. The next prime is 1618605671. The reversal of 1618605665 is 5665068161.

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 1618605665 - 2² = 1618605661 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1618605661) 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, 335519 + ... + 340308.

It is an arithmetic number, because the mean of its divisors is an integer number (243298080).

Almost surely, 2^1618605665 is an apocalyptic number.

It is an amenable number.

1618605665 is a deficient number, since it is larger than the sum of its proper divisors (327778975).

1618605665 is an equidigital number, since it uses as much as digits as its factorization.

1618605665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 676311.

The product of its (nonzero) digits is 259200, while the sum is 44.

The square root of 1618605665 is about 40231.8986004886. The cubic root of 1618605665 is about 1174.1232427330.

The spelling of 1618605665 in words is "one billion, six hundred eighteen million, six hundred five thousand, six hundred sixty-five".