61685581318 has 16 divisors (see below), whose sum is σ = 94100133456. Its totient is φ = 30319460640.

The previous prime is 61685581283. The next prime is 61685581339. The reversal of 61685581318 is 81318558616.

It is a happy number.

It is a super-2 number, since 2×61685581318² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 63480 + ... + 356932.

It is an arithmetic number, because the mean of its divisors is an integer number (5881258341).

Almost surely, 2^61685581318 is an apocalyptic number.

61685581318 is a deficient number, since it is larger than the sum of its proper divisors (32414552138).

61685581318 is a wasteful number, since it uses less digits than its factorization.

61685581318 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 295239.

The product of its digits is 1382400, while the sum is 52.

The spelling of 61685581318 in words is "sixty-one billion, six hundred eighty-five million, five hundred eighty-one thousand, three hundred eighteen".