55442220 has 24 divisors (see below), whose sum is σ = 155238384. Its totient is φ = 14784576.

The previous prime is 55442203. The next prime is 55442239. The reversal of 55442220 is 2224455.

It is a happy number.

It is a super-4 number, since 4×55442220⁴ (a number of 32 digits) contains 4444 as substring.

It is a nialpdrome in base 10.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 461959 + ... + 462078.

It is an arithmetic number, because the mean of its divisors is an integer number (6468266).

Almost surely, 2^55442220 is an apocalyptic number.

It is an amenable number.

55442220 is an abundant number, since it is smaller than the sum of its proper divisors (99796164).

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

55442220 is a wasteful number, since it uses less digits than its factorization.

55442220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 924049 (or 924047 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 24.

The square root of 55442220 is about 7445.9532633505. The cubic root of 55442220 is about 381.3117638894.

Adding to 55442220 its reverse (2224455), we get a palindrome (57666675).

The spelling of 55442220 in words is "fifty-five million, four hundred forty-two thousand, two hundred twenty".