55437840 has 120 divisors (see below), whose sum is σ = 191302488. Its totient is φ = 14376960.

The previous prime is 55437829. The next prime is 55437847. The reversal of 55437840 is 4873455.

55437840 is a `hidden beast` number, since 5 + 543 + 78 + 40 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 12194064 + 43243776 = 3492^2 + 6576^2 .

It is a tau number, because it is divible by the number of its divisors (120).

It is a super-3 number, since 3×55437840³ (a number of 24 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 55437795 and 55437804.

It is not an unprimeable number, because it can be changed into a prime (55437847) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 25600 + ... + 27680.

Almost surely, 2^55437840 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 55437840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (95651244).

55437840 is an abundant number, since it is smaller than the sum of its proper divisors (135864648).

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

55437840 is a wasteful number, since it uses less digits than its factorization.

55437840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2137 (or 2128 counting only the distinct ones).

The product of its (nonzero) digits is 67200, while the sum is 36.

The square root of 55437840 is about 7445.6591380482. The cubic root of 55437840 is about 381.3017222670.

The spelling of 55437840 in words is "fifty-five million, four hundred thirty-seven thousand, eight hundred forty".