61816780800 has 576 divisors, whose sum is σ = 229902472800. Its totient is φ = 16279142400.

The previous prime is 61816780769. The next prime is 61816780807. The reversal of 61816780800 is 808761816.

It is a tau number, because it is divible by the number of its divisors (576).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61816780807) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 134092570 + ... + 134093030.

Almost surely, 2^61816780800 is an apocalyptic number.

61816780800 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 61816780800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (114951236400).

61816780800 is an abundant number, since it is smaller than the sum of its proper divisors (168085692000).

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

61816780800 is a wasteful number, since it uses less digits than its factorization.

61816780800 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 599 (or 568 counting only the distinct ones).

The product of its (nonzero) digits is 129024, while the sum is 45.

The spelling of 61816780800 in words is "sixty-one billion, eight hundred sixteen million, seven hundred eighty thousand, eight hundred".