61518161 has 4 divisors (see below), whose sum is σ = 63180852. Its totient is φ = 59855472.

The previous prime is 61518157. The next prime is 61518173. The reversal of 61518161 is 16181516.

61518161 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 52780225 + 8737936 = 7265^2 + 2956^2 .

It is a cyclic number.

It is not a de Polignac number, because 61518161 - 2² = 61518157 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (61518101) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 831290 + ... + 831363.

It is an arithmetic number, because the mean of its divisors is an integer number (15795213).

Almost surely, 2^61518161 is an apocalyptic number.

It is an amenable number.

61518161 is a deficient number, since it is larger than the sum of its proper divisors (1662691).

61518161 is a wasteful number, since it uses less digits than its factorization.

61518161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1662690.

The product of its digits is 1440, while the sum is 29.

The square root of 61518161 is about 7843.3513882778. The cubic root of 61518161 is about 394.7611887670.

Adding to 61518161 its reverse (16181516), we get a palindrome (77699677).

The spelling of 61518161 in words is "sixty-one million, five hundred eighteen thousand, one hundred sixty-one".