61123636512 has 144 divisors (see below), whose sum is σ = 179058435192. Its totient is φ = 19763896320.

The previous prime is 61123636507. The next prime is 61123636529. The reversal of 61123636512 is 21563632116.

61123636512 is a `hidden beast` number, since 6 + 1 + 1 + 2 + 3 + 636 + 5 + 12 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 61090042896 + 33593616 = 247164^2 + 5796^2 .

It is a tau number, because it is divible by the number of its divisors (144).

It is a super-2 number, since 2×61123636512² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

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, 3582562 + ... + 3599582.

Almost surely, 2^61123636512 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 61123636512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (89529217596).

61123636512 is an abundant number, since it is smaller than the sum of its proper divisors (117934798680).

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

61123636512 is a wasteful number, since it uses less digits than its factorization.

61123636512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17411 (or 17400 counting only the distinct ones).

The product of its digits is 38880, while the sum is 36.

The spelling of 61123636512 in words is "sixty-one billion, one hundred twenty-three million, six hundred thirty-six thousand, five hundred twelve".