55305978 has 32 divisors (see below), whose sum is σ = 136139136. Its totient is φ = 14586048.

The previous prime is 55305967. The next prime is 55305983. The reversal of 55305978 is 87950355.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50101 + ... + 51192.

It is an arithmetic number, because the mean of its divisors is an integer number (4254348).

Almost surely, 2^55305978 is an apocalyptic number.

55305978 is an abundant number, since it is smaller than the sum of its proper divisors (80833158).

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

55305978 is a wasteful number, since it uses less digits than its factorization.

55305978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101318.

The product of its (nonzero) digits is 189000, while the sum is 42.

The square root of 55305978 is about 7436.7989081324. The cubic root of 55305978 is about 380.9991664410. Note that the first 3 decimals are identical.

The spelling of 55305978 in words is "fifty-five million, three hundred five thousand, nine hundred seventy-eight".