7081661 has 4 divisors (see below), whose sum is σ = 7454400. Its totient is φ = 6708924.

The previous prime is 7081649. The next prime is 7081663. The reversal of 7081661 is 1661807.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1661807 = 7 ⋅237401.

It is a cyclic number.

It is not a de Polignac number, because 7081661 - 2¹⁴ = 7065277 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7081663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 186341 + ... + 186378.

It is an arithmetic number, because the mean of its divisors is an integer number (1863600).

Almost surely, 2^7081661 is an apocalyptic number.

It is an amenable number.

7081661 is a deficient number, since it is larger than the sum of its proper divisors (372739).

7081661 is a wasteful number, since it uses less digits than its factorization.

7081661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 372738.

The product of its (nonzero) digits is 2016, while the sum is 29.

The square root of 7081661 is about 2661.1390418390. The cubic root of 7081661 is about 192.0341103315.

The spelling of 7081661 in words is "seven million, eighty-one thousand, six hundred sixty-one".