55407240 has 240 divisors, whose sum is σ = 217255500. Its totient is φ = 12628224.

The previous prime is 55407239. The next prime is 55407251. The reversal of 55407240 is 4270455.

55407240 is a `hidden beast` number, since 554 + 0 + 72 + 40 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 55264356 + 142884 = 7434^2 + 378^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is an unprimeable number.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 158586 + ... + 158934.

Almost surely, 2^55407240 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 55407240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (108627750).

55407240 is an abundant number, since it is smaller than the sum of its proper divisors (161848260).

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

55407240 is a wasteful number, since it uses less digits than its factorization.

55407240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 386 (or 366 counting only the distinct ones).

The product of its (nonzero) digits is 5600, while the sum is 27.

The square root of 55407240 is about 7443.6039658219. The cubic root of 55407240 is about 381.2315537075.

Adding to 55407240 its reverse (4270455), we get a palindrome (59677695).

The spelling of 55407240 in words is "fifty-five million, four hundred seven thousand, two hundred forty".