55402240 has 36 divisors (see below), whose sum is σ = 132708744. Its totient is φ = 22160384.

The previous prime is 55402231. The next prime is 55402247. The reversal of 55402240 is 4220455.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55402247) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20362 + ... + 22921.

It is an arithmetic number, because the mean of its divisors is an integer number (3686354).

Almost surely, 2^55402240 is an apocalyptic number.

It is an amenable number.

55402240 is an abundant number, since it is smaller than the sum of its proper divisors (77306504).

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

55402240 is an equidigital number, since it uses as much as digits as its factorization.

55402240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43304 (or 43290 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 22.

The square root of 55402240 is about 7443.2680994305. The cubic root of 55402240 is about 381.2200858012.

Adding to 55402240 its reverse (4220455), we get a palindrome (59622695).

The spelling of 55402240 in words is "fifty-five million, four hundred two thousand, two hundred forty".