55140440 has 16 divisors (see below), whose sum is σ = 124066080. Its totient is φ = 22056160.

The previous prime is 55140439. The next prime is 55140457. The reversal of 55140440 is 4404155.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 689216 + ... + 689295.

It is an arithmetic number, because the mean of its divisors is an integer number (7754130).

Almost surely, 2^55140440 is an apocalyptic number.

It is an amenable number.

55140440 is an abundant number, since it is smaller than the sum of its proper divisors (68925640).

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

55140440 is a wasteful number, since it uses less digits than its factorization.

55140440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1378522 (or 1378518 counting only the distinct ones).

The product of its (nonzero) digits is 1600, while the sum is 23.

The square root of 55140440 is about 7425.6609133464. The cubic root of 55140440 is about 380.6186598329.

Adding to 55140440 its reverse (4404155), we get a palindrome (59544595).

The spelling of 55140440 in words is "fifty-five million, one hundred forty thousand, four hundred forty".