55661611500 has 288 divisors, whose sum is σ = 201642255360. Its totient is φ = 12783312000.

The previous prime is 55661611471. The next prime is 55661611501. The reversal of 55661611500 is 511616655.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (55661611501) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 910909 + ... + 970091.

It is an arithmetic number, because the mean of its divisors is an integer number (700146720).

Almost surely, 2^55661611500 is an apocalyptic number.

55661611500 is a gapful number since it is divisible by the number (50) 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 55661611500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (100821127680).

55661611500 is an abundant number, since it is smaller than the sum of its proper divisors (145980643860).

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

55661611500 is a wasteful number, since it uses less digits than its factorization.

55661611500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59238 (or 59223 counting only the distinct ones).

The product of its (nonzero) digits is 27000, while the sum is 36.

The spelling of 55661611500 in words is "fifty-five billion, six hundred sixty-one million, six hundred eleven thousand, five hundred".