5651661 has 8 divisors (see below), whose sum is σ = 7591104. Its totient is φ = 3740000.

The previous prime is 5651623. The next prime is 5651707. The reversal of 5651661 is 1661565.

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 5651661 - 2¹⁰ = 5650637 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5651621) 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 7 ways as a sum of consecutive naturals, for example, 6465 + ... + 7286.

It is an arithmetic number, because the mean of its divisors is an integer number (948888).

Almost surely, 2^5651661 is an apocalyptic number.

It is an amenable number.

5651661 is a deficient number, since it is larger than the sum of its proper divisors (1939443).

5651661 is a wasteful number, since it uses less digits than its factorization.

5651661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13891.

The product of its digits is 5400, while the sum is 30.

The square root of 5651661 is about 2377.3222331018. The cubic root of 5651661 is about 178.1252012309.

The spelling of 5651661 in words is "five million, six hundred fifty-one thousand, six hundred sixty-one".