1618558161 has 16 divisors (see below), whose sum is σ = 2354946048. Its totient is φ = 980661200.

The previous prime is 1618558157. The next prime is 1618558217.

1618558161 is nontrivially palindromic in base 10.

It is a cyclic number.

It is not a de Polignac number, because 1618558161 - 2² = 1618558157 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1618558861) 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, 195496 + ... + 203606.

It is an arithmetic number, because the mean of its divisors is an integer number (147184128).

Almost surely, 2^1618558161 is an apocalyptic number.

1618558161 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1618558161 is a deficient number, since it is larger than the sum of its proper divisors (736387887).

1618558161 is a wasteful number, since it uses less digits than its factorization.

1618558161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14172.

The product of its digits is 57600, while the sum is 42.

The square root of 1618558161 is about 40231.3082188487. The cubic root of 1618558161 is about 1174.1117562836. Note that the first 3 decimals are identical.

The spelling of 1618558161 in words is "one billion, six hundred eighteen million, five hundred fifty-eight thousand, one hundred sixty-one".