61681218 has 16 divisors (see below), whose sum is σ = 124150080. Its totient is φ = 20429136.

The previous prime is 61681181. The next prime is 61681237. The reversal of 61681218 is 81218616.

61681218 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 31798 + ... + 33681.

It is an arithmetic number, because the mean of its divisors is an integer number (7759380).

Almost surely, 2^61681218 is an apocalyptic number.

61681218 is an abundant number, since it is smaller than the sum of its proper divisors (62468862).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61681218 is a wasteful number, since it uses less digits than its factorization.

61681218 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65641.

The product of its digits is 4608, while the sum is 33.

The square root of 61681218 is about 7853.7391094943. The cubic root of 61681218 is about 395.1096592402.

The spelling of 61681218 in words is "sixty-one million, six hundred eighty-one thousand, two hundred eighteen".