55415520 has 144 divisors (see below), whose sum is σ = 195773760. Its totient is φ = 14257152.

The previous prime is 55415501. The next prime is 55415537. The reversal of 55415520 is 2551455.

It is a tau number, because it is divible by the number of its divisors (144).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 41097 + ... + 42423.

It is an arithmetic number, because the mean of its divisors is an integer number (1359540).

Almost surely, 2^55415520 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 55415520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (97886880).

55415520 is an abundant number, since it is smaller than the sum of its proper divisors (140358240).

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

55415520 is a wasteful number, since it uses less digits than its factorization.

55415520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1377 (or 1366 counting only the distinct ones).

The product of its (nonzero) digits is 5000, while the sum is 27.

The square root of 55415520 is about 7444.1601272407. The cubic root of 55415520 is about 381.2505430432.

Adding to 55415520 its reverse (2551455), we get a palindrome (57966975).

The spelling of 55415520 in words is "fifty-five million, four hundred fifteen thousand, five hundred twenty".