55278520 has 64 divisors (see below), whose sum is σ = 137622240. Its totient is φ = 19814400.

The previous prime is 55278511. The next prime is 55278529. The reversal of 55278520 is 2587255.

It is an interprime number because it is at equal distance from previous prime (55278511) and next prime (55278529).

It is a Smith number, since the sum of its digits (34) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55278529) 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, 31260 + ... + 32980.

Almost surely, 2^55278520 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 55278520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (68811120).

55278520 is an abundant number, since it is smaller than the sum of its proper divisors (82343720).

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

55278520 is a wasteful number, since it uses less digits than its factorization.

55278520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1816 (or 1812 counting only the distinct ones).

The product of its (nonzero) digits is 28000, while the sum is 34.

The square root of 55278520 is about 7434.9525889544. The cubic root of 55278520 is about 380.9361038978.

The spelling of 55278520 in words is "fifty-five million, two hundred seventy-eight thousand, five hundred twenty".