61315256470640 has 40 divisors (see below), whose sum is σ = 142653841087680. Its totient is φ = 24509608860416.

The previous prime is 61315256470639. The next prime is 61315256470649. The reversal of 61315256470640 is 4607465251316.

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61315256470649) 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 7 ways as a sum of consecutive naturals, for example, 257594795 + ... + 257832714.

It is an arithmetic number, because the mean of its divisors is an integer number (3566346027192).

Almost surely, 2^{61315256470640} is an apocalyptic number.

It is an amenable number.

61315256470640 is an abundant number, since it is smaller than the sum of its proper divisors (81338584617040).

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

61315256470640 is a wasteful number, since it uses less digits than its factorization.

61315256470640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 515429009 (or 515429003 counting only the distinct ones).

The product of its (nonzero) digits is 3628800, while the sum is 50.

The spelling of 61315256470640 in words is "sixty-one trillion, three hundred fifteen billion, two hundred fifty-six million, four hundred seventy thousand, six hundred forty".