86661555 has 16 divisors (see below), whose sum is σ = 141884160. Its totient is φ = 45144288.

The previous prime is 86661551. The next prime is 86661557. The reversal of 86661555 is 55516668.

It is not a de Polignac number, because 86661555 - 2² = 86661551 is a prime.

It is not an unprimeable number, because it can be changed into a prime (86661551) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 66535 + ... + 67824.

It is an arithmetic number, because the mean of its divisors is an integer number (8867760).

Almost surely, 2^86661555 is an apocalyptic number.

86661555 is a deficient number, since it is larger than the sum of its proper divisors (55222605).

86661555 is a wasteful number, since it uses less digits than its factorization.

86661555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 134410.

The product of its digits is 216000, while the sum is 42.

The square root of 86661555 is about 9309.2188179245. The cubic root of 86661555 is about 442.5294308364.

The spelling of 86661555 in words is "eighty-six million, six hundred sixty-one thousand, five hundred fifty-five".