55246640 has 20 divisors (see below), whose sum is σ = 128448624. Its totient is φ = 22098624.

The previous prime is 55246603. The next prime is 55246643. The reversal of 55246640 is 4664255.

It is a tau number, because it is divible by the number of its divisors (20).

It is a super-4 number, since 4×55246640⁴ (a number of 32 digits) contains 4444 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 55246597 and 55246606.

It is not an unprimeable number, because it can be changed into a prime (55246643) 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, 345212 + ... + 345371.

Almost surely, 2^55246640 is an apocalyptic number.

It is an amenable number.

55246640 is an abundant number, since it is smaller than the sum of its proper divisors (73201984).

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

55246640 is a wasteful number, since it uses less digits than its factorization.

55246640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 690596 (or 690590 counting only the distinct ones).

The product of its (nonzero) digits is 28800, while the sum is 32.

The square root of 55246640 is about 7432.8083521641. The cubic root of 55246640 is about 380.8628591828.

The spelling of 55246640 in words is "fifty-five million, two hundred forty-six thousand, six hundred forty".