7661655 has 64 divisors (see below), whose sum is σ = 14976000. Its totient is φ = 3701376.

The previous prime is 7661639. The next prime is 7661663. The reversal of 7661655 is 5561667.

It is a happy number.

7661655 is a nontrivial binomial coefficient, being equal to C(3915, 2).

It is not a de Polignac number, because 7661655 - 2⁴ = 7661639 is a prime.

7661655 is a lucky number.

It is a congruent number.

It is an unprimeable number.

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 63 ways as a sum of consecutive naturals, for example, 74334 + ... + 74436.

It is an arithmetic number, because the mean of its divisors is an integer number (234000).

Almost surely, 2^7661655 is an apocalyptic number.

7661655 is the 3914-th triangular number.

7661655 is a deficient number, since it is larger than the sum of its proper divisors (7314345).

7661655 is a wasteful number, since it uses less digits than its factorization.

With its predecessor (7661654) it forms a Ruth-Aaron pair, since the sum of their prime factors is the same (165).

7661655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165 (or 159 counting only the distinct ones).

The product of its digits is 37800, while the sum is 36.

The square root of 7661655 is about 2767.9694723750. The cubic root of 7661655 is about 197.1397481281.

The spelling of 7661655 in words is "seven million, six hundred sixty-one thousand, six hundred fifty-five".