61881697512 has 48 divisors (see below), whose sum is σ = 176417124000. Its totient is φ = 19541588256.

The previous prime is 61881697499. The next prime is 61881697517. The reversal of 61881697512 is 21579618816.

It is a happy number.

61881697512 is a `hidden beast` number, since 61 + 8 + 8 + 1 + 69 + 7 + 512 = 666.

It is not an unprimeable number, because it can be changed into a prime (61881697517) by changing a digit.

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 11 ways as a sum of consecutive naturals, for example, 22616212 + ... + 22618947.

It is an arithmetic number, because the mean of its divisors is an integer number (3675356750).

Almost surely, 2^61881697512 is an apocalyptic number.

It is an amenable number.

61881697512 is an abundant number, since it is smaller than the sum of its proper divisors (114535426488).

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

61881697512 is a wasteful number, since it uses less digits than its factorization.

61881697512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45235190 (or 45235183 counting only the distinct ones).

The product of its digits is 1451520, while the sum is 54.

The spelling of 61881697512 in words is "sixty-one billion, eight hundred eighty-one million, six hundred ninety-seven thousand, five hundred twelve".