55212520 has 64 divisors (see below), whose sum is σ = 140227200. Its totient is φ = 19380480.

The previous prime is 55212467. The next prime is 55212523. The reversal of 55212520 is 2521255.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 55212491 and 55212500.

It is not an unprimeable number, because it can be changed into a prime (55212523) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10597 + ... + 14923.

It is an arithmetic number, because the mean of its divisors is an integer number (2191050).

Almost surely, 2^55212520 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 55212520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (70113600).

55212520 is an abundant number, since it is smaller than the sum of its proper divisors (85014680).

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

55212520 is a wasteful number, since it uses less digits than its factorization.

55212520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4378 (or 4374 counting only the distinct ones).

The product of its (nonzero) digits is 1000, while the sum is 22.

The square root of 55212520 is about 7430.5127683088. The cubic root of 55212520 is about 380.7844368154.

Adding to 55212520 its reverse (2521255), we get a palindrome (57733775).

The spelling of 55212520 in words is "fifty-five million, two hundred twelve thousand, five hundred twenty".