55031280 has 80 divisors (see below), whose sum is σ = 171310464. Its totient is φ = 14613760.

The previous prime is 55031279. The next prime is 55031287. The reversal of 55031280 is 8213055.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 55031280.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55031287) 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, 111835 + ... + 112325.

Almost surely, 2^55031280 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 55031280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (85655232).

55031280 is an abundant number, since it is smaller than the sum of its proper divisors (116279184).

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

55031280 is a wasteful number, since it uses less digits than its factorization.

55031280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 974 (or 968 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 24.

The square root of 55031280 is about 7418.3070845038. The cubic root of 55031280 is about 380.3673271724.

The spelling of 55031280 in words is "fifty-five million, thirty-one thousand, two hundred eighty".