61534561536 has 216 divisors, whose sum is σ = 209307431424. Its totient is φ = 17014026240.

The previous prime is 61534561507. The next prime is 61534561541. The reversal of 61534561536 is 63516543516.

It is a happy number.

61534561536 is a `hidden beast` number, since 6 + 1 + 5 + 34 + 561 + 53 + 6 = 666.

61534561536 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 61534561491 and 61534561500.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 438430 + ... + 561506.

Almost surely, 2^61534561536 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61534561536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (104653715712).

61534561536 is an abundant number, since it is smaller than the sum of its proper divisors (147772869888).

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

61534561536 is a wasteful number, since it uses less digits than its factorization.

61534561536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123137 (or 123120 counting only the distinct ones).

The product of its digits is 972000, while the sum is 45.

The spelling of 61534561536 in words is "sixty-one billion, five hundred thirty-four million, five hundred sixty-one thousand, five hundred thirty-six".