61945228800 has 1440 divisors, whose sum is σ = 288126558720. Its totient is φ = 12342067200.

The previous prime is 61945228757. The next prime is 61945228841. The reversal of 61945228800 is 882254916.

61945228800 is a `hidden beast` number, since 619 + 4 + 5 + 2 + 28 + 8 + 0 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (1440).

It is a super-2 number, since 2×61945228800² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 199180645 + ... + 199180955.

It is an arithmetic number, because the mean of its divisors is an integer number (200087888).

Almost surely, 2^61945228800 is an apocalyptic number.

61945228800 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61945228800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (144063279360).

61945228800 is an abundant number, since it is smaller than the sum of its proper divisors (226181329920).

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

61945228800 is a wasteful number, since it uses less digits than its factorization.

61945228800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 384 (or 360 counting only the distinct ones).

The product of its (nonzero) digits is 276480, while the sum is 45.

The spelling of 61945228800 in words is "sixty-one billion, nine hundred forty-five million, two hundred twenty-eight thousand, eight hundred".