55561897500 has 120 divisors (see below), whose sum is σ = 167590666320. Its totient is φ = 14305536000.

The previous prime is 55561897483. The next prime is 55561897537. The reversal of 55561897500 is 579816555.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 89772 + ... + 345228.

It is an arithmetic number, because the mean of its divisors is an integer number (1396588886).

Almost surely, 2^55561897500 is an apocalyptic number.

55561897500 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 55561897500, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (83795333160).

55561897500 is an abundant number, since it is smaller than the sum of its proper divisors (112028768820).

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

55561897500 is a wasteful number, since it uses less digits than its factorization.

55561897500 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 255513 (or 255496 counting only the distinct ones).

The product of its (nonzero) digits is 1890000, while the sum is 51.

The spelling of 55561897500 in words is "fifty-five billion, five hundred sixty-one million, eight hundred ninety-seven thousand, five hundred".