1661600055 has 16 divisors (see below), whose sum is σ = 2679496704. Its totient is φ = 879207840.

The previous prime is 1661600053. The next prime is 1661600113. The reversal of 1661600055 is 5500061661.

It is not a de Polignac number, because 1661600055 - 2¹ = 1661600053 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1661599995 and 1661600031.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661600053) 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, 434211 + ... + 438020.

It is an arithmetic number, because the mean of its divisors is an integer number (167468544).

Almost surely, 2^1661600055 is an apocalyptic number.

1661600055 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1661600055 is a deficient number, since it is larger than the sum of its proper divisors (1017896649).

1661600055 is a wasteful number, since it uses less digits than its factorization.

1661600055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 872366.

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

The square root of 1661600055 is about 40762.7287482082. The cubic root of 1661600055 is about 1184.4284555299.

The spelling of 1661600055 in words is "one billion, six hundred sixty-one million, six hundred thousand, fifty-five".