61081639610 has 16 divisors (see below), whose sum is σ = 110684853000. Its totient is φ = 24268677696.

The previous prime is 61081639571. The next prime is 61081639613. The reversal of 61081639610 is 1693618016.

It is a Cunningham number, because it is equal to 247147²+1.

It can be written as a sum of positive squares in 4 ways, for example, as 21989627521 + 39092012089 = 148289^2 + 197717^2 .

It is not an unprimeable number, because it can be changed into a prime (61081639613) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20495705 + ... + 20498684.

Almost surely, 2^61081639610 is an apocalyptic number.

61081639610 is a deficient number, since it is larger than the sum of its proper divisors (49603213390).

61081639610 is a wasteful number, since it uses less digits than its factorization.

61081639610 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40994545.

The product of its (nonzero) digits is 46656, while the sum is 41.

The spelling of 61081639610 in words is "sixty-one billion, eighty-one million, six hundred thirty-nine thousand, six hundred ten".