55681340 has 48 divisors (see below), whose sum is σ = 137380320. Its totient is φ = 18689280.

The previous prime is 55681331. The next prime is 55681357. The reversal of 55681340 is 4318655.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 55681297 and 55681306.

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, 6875 + ... + 12594.

It is an arithmetic number, because the mean of its divisors is an integer number (2862090).

Almost surely, 2^55681340 is an apocalyptic number.

It is an amenable number.

55681340 is an abundant number, since it is smaller than the sum of its proper divisors (81698980).

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

55681340 is a wasteful number, since it uses less digits than its factorization.

55681340 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19502 (or 19500 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 32.

The square root of 55681340 is about 7461.9930313556. The cubic root of 55681340 is about 381.8591716112.

Adding to 55681340 its reverse (4318655), we get a palindrome (59999995).

The spelling of 55681340 in words is "fifty-five million, six hundred eighty-one thousand, three hundred forty".