8155661 has 4 divisors (see below), whose sum is σ = 8209824. Its totient is φ = 8101500.

The previous prime is 8155657. The next prime is 8155669. The reversal of 8155661 is 1665518.

It is a happy number.

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.

It is a cyclic number.

It is not a de Polignac number, because 8155661 - 2² = 8155657 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8155669) 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, 26855 + ... + 27156.

It is an arithmetic number, because the mean of its divisors is an integer number (2052456).

Almost surely, 2^8155661 is an apocalyptic number.

It is an amenable number.

8155661 is a deficient number, since it is larger than the sum of its proper divisors (54163).

8155661 is a wasteful number, since it uses less digits than its factorization.

8155661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54162.

The product of its digits is 7200, while the sum is 32.

The square root of 8155661 is about 2855.8117935186. The cubic root of 8155661 is about 201.2888514681.

The spelling of 8155661 in words is "eight million, one hundred fifty-five thousand, six hundred sixty-one".