1611681 has 8 divisors (see below), whose sum is σ = 2184384. Its totient is φ = 1056720.

The previous prime is 1611667. The next prime is 1611689. The reversal of 1611681 is 1861161.

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

It is not a de Polignac number, because 1611681 - 2⁷ = 1611553 is a prime.

It is a super-2 number, since 2×1611681² = 5195031291522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1611689) 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, 4221 + ... + 4586.

It is an arithmetic number, because the mean of its divisors is an integer number (273048).

2^1611681 is an apocalyptic number.

It is an amenable number.

1611681 is a deficient number, since it is larger than the sum of its proper divisors (572703).

1611681 is an equidigital number, since it uses as much as digits as its factorization.

1611681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8871.

The product of its digits is 288, while the sum is 24.

The square root of 1611681 is about 1269.5199880270. The cubic root of 1611681 is about 117.2446484283.

The spelling of 1611681 in words is "one million, six hundred eleven thousand, six hundred eighty-one".