55775778 has 8 divisors (see below), whose sum is σ = 111551568. Its totient is φ = 18591924.

The previous prime is 55775771. The next prime is 55775779. The reversal of 55775778 is 87757755.

It is a sphenic number, since it is the product of 3 distinct primes.

55775778 is an admirable number.

It is a super-2 number, since 2×55775778² = 6221874823010568, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 55775778.

It is not an unprimeable number, because it can be changed into a prime (55775771) 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, 4647976 + ... + 4647987.

It is an arithmetic number, because the mean of its divisors is an integer number (13943946).

Almost surely, 2^55775778 is an apocalyptic number.

55775778 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

55775778 is a wasteful number, since it uses less digits than its factorization.

55775778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9295968.

The product of its digits is 2401000, while the sum is 51.

The square root of 55775778 is about 7468.3182845939. The cubic root of 55775778 is about 382.0749329899.

The spelling of 55775778 in words is "fifty-five million, seven hundred seventy-five thousand, seven hundred seventy-eight".