55961840 has 80 divisors (see below), whose sum is σ = 149454720. Its totient is φ = 19272960.

The previous prime is 55961833. The next prime is 55961863. The reversal of 55961840 is 4816955.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (38).

It is a junction number, because it is equal to n+sod(n) for n = 55961794 and 55961803.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15047 + ... + 18393.

It is an arithmetic number, because the mean of its divisors is an integer number (1868184).

Almost surely, 2^55961840 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 55961840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (74727360).

55961840 is an abundant number, since it is smaller than the sum of its proper divisors (93492880).

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

55961840 is a wasteful number, since it uses less digits than its factorization.

55961840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3390 (or 3384 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 38.

The square root of 55961840 is about 7480.7646667971. The cubic root of 55961840 is about 382.4993150770.

The spelling of 55961840 in words is "fifty-five million, nine hundred sixty-one thousand, eight hundred forty".