1617997 has 4 divisors (see below), whose sum is σ = 1673820. Its totient is φ = 1562176.

The previous prime is 1617989. The next prime is 1618003. The reversal of 1617997 is 7997161.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7997161 = 61 ⋅131101.

It can be written as a sum of positive squares in 2 ways, for example, as 427716 + 1190281 = 654^2 + 1091^2 .

It is a cyclic number.

It is not a de Polignac number, because 1617997 - 2³ = 1617989 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 a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1617977) 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, 27868 + ... + 27925.

It is an arithmetic number, because the mean of its divisors is an integer number (418455).

2^1617997 is an apocalyptic number.

It is an amenable number.

1617997 is a deficient number, since it is larger than the sum of its proper divisors (55823).

1617997 is an equidigital number, since it uses as much as digits as its factorization.

1617997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55822.

The product of its digits is 23814, while the sum is 40.

The square root of 1617997 is about 1272.0051100526. The cubic root of 1617997 is about 117.3976050752.

The spelling of 1617997 in words is "one million, six hundred seventeen thousand, nine hundred ninety-seven".