61643212450 has 24 divisors (see below), whose sum is σ = 114857933220. Its totient is φ = 24613939200.

The previous prime is 61643212441. The next prime is 61643212451. The reversal of 61643212450 is 5421234616.

It can be written as a sum of positive squares in 6 ways, for example, as 5707651401 + 55935561049 = 75549^2 + 236507^2 .

It is not an unprimeable number, because it can be changed into a prime (61643212451) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1054911 + ... + 1111810.

Almost surely, 2^61643212450 is an apocalyptic number.

61643212450 is a deficient number, since it is larger than the sum of its proper divisors (53214720770).

61643212450 is a wasteful number, since it uses less digits than its factorization.

61643212450 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2167302 (or 2167297 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 34.

The spelling of 61643212450 in words is "sixty-one billion, six hundred forty-three million, two hundred twelve thousand, four hundred fifty".