55517400 has 240 divisors, whose sum is σ = 202554000. Its totient is φ = 14065920.

The previous prime is 55517389. The next prime is 55517417. The reversal of 55517400 is 471555.

It is a Cunningham number, because it is equal to 7451²-1.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 372526 + ... + 372674.

It is an arithmetic number, because the mean of its divisors is an integer number (843975).

Almost surely, 2^55517400 is an apocalyptic number.

55517400 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 55517400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (101277000).

55517400 is an abundant number, since it is smaller than the sum of its proper divisors (147036600).

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

55517400 is a wasteful number, since it uses less digits than its factorization.

55517400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 200 (or 182 counting only the distinct ones).

The product of its (nonzero) digits is 3500, while the sum is 27.

The square root of 55517400 is about 7450.9999328949. Note that the first 4 decimals coincide. The cubic root of 55517400 is about 381.4840397627.

Adding to 55517400 its reverse (471555), we get a palindrome (55988955).

It can be divided in two parts, 555 and 17400, that added together give a triangular number (17955 = T₁₈₉).

The spelling of 55517400 in words is "fifty-five million, five hundred seventeen thousand, four hundred".