61787019636 has 36 divisors (see below), whose sum is σ = 161569508100. Its totient is φ = 19885477248.

The previous prime is 61787019629. The next prime is 61787019649. The reversal of 61787019636 is 63691078716.

It is a happy number.

61787019636 is a `hidden beast` number, since 617 + 8 + 7 + 0 + 19 + 6 + 3 + 6 = 666.

61787019636 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 28626609636 + 33160410000 = 169194^2 + 182100^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 29590441 + ... + 29592528.

Almost surely, 2^61787019636 is an apocalyptic number.

It is an amenable number.

61787019636 is an abundant number, since it is smaller than the sum of its proper divisors (99782488464).

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

61787019636 is a wasteful number, since it uses less digits than its factorization.

61787019636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59183008 (or 59183003 counting only the distinct ones).

The product of its (nonzero) digits is 2286144, while the sum is 54.

The spelling of 61787019636 in words is "sixty-one billion, seven hundred eighty-seven million, nineteen thousand, six hundred thirty-six".