1661500055 has 8 divisors (see below), whose sum is σ = 2036221632. Its totient is φ = 1300919008.

The previous prime is 1661500051. The next prime is 1661500067. The reversal of 1661500055 is 5500051661.

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 1661500055 - 2² = 1661500051 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 (1661500051) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3534872 + ... + 3535341.

It is an arithmetic number, because the mean of its divisors is an integer number (254527704).

Almost surely, 2^1661500055 is an apocalyptic number.

1661500055 is a deficient number, since it is larger than the sum of its proper divisors (374721577).

1661500055 is an equidigital number, since it uses as much as digits as its factorization.

1661500055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7070265.

The product of its (nonzero) digits is 4500, while the sum is 29.

The square root of 1661500055 is about 40761.5021190338. The cubic root of 1661500055 is about 1184.4046942521.

The spelling of 1661500055 in words is "one billion, six hundred sixty-one million, five hundred thousand, fifty-five".