55145840 has 40 divisors (see below), whose sum is σ = 128750688. Its totient is φ = 21966080.

The previous prime is 55145837. The next prime is 55145843. The reversal of 55145840 is 4854155.

55145840 = T₁₆₉ + T₁₇₀ + ... + T₆₉₄.

55145840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (55145837) and next prime (55145843).

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 55145797 and 55145806.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (55145843) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19730 + ... + 22350.

Almost surely, 2^55145840 is an apocalyptic number.

It is an amenable number.

55145840 is an abundant number, since it is smaller than the sum of its proper divisors (73604848).

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

55145840 is a wasteful number, since it uses less digits than its factorization.

55145840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2897 (or 2891 counting only the distinct ones).

The product of its (nonzero) digits is 16000, while the sum is 32.

The square root of 55145840 is about 7426.0245084433. The cubic root of 55145840 is about 380.6310843117.

Adding to 55145840 its reverse (4854155), we get a palindrome (59999995).

The spelling of 55145840 in words is "fifty-five million, one hundred forty-five thousand, eight hundred forty".