61489874787840 has 400 divisors, whose sum is σ = 231828754219920. Its totient is φ = 15534283161600.

The previous prime is 61489874787811. The next prime is 61489874787841. The reversal of 61489874787840 is 4878747898416.

61489874787840 is a `hidden beast` number, since 6 + 14 + 8 + 98 + 7 + 478 + 7 + 8 + 40 = 666.

61489874787840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is a self number, because there is not a number n which added to its sum of digits gives 61489874787840.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61489874787841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 3863761 + ... + 11743440.

Almost surely, 2^{61489874787840} is an apocalyptic number.

61489874787840 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

61489874787840 is an abundant number, since it is smaller than the sum of its proper divisors (170338879432080).

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

61489874787840 is a wasteful number, since it uses less digits than its factorization.

61489874787840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15607255 (or 15607230 counting only the distinct ones).

The product of its (nonzero) digits is 4855431168, while the sum is 81.

The spelling of 61489874787840 in words is "sixty-one trillion, four hundred eighty-nine billion, eight hundred seventy-four million, seven hundred eighty-seven thousand, eight hundred forty".