55577778 has 8 divisors (see below), whose sum is σ = 111155568. Its totient is φ = 18525924.

The previous prime is 55577719. The next prime is 55577789. The reversal of 55577778 is 87777555.

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

55577778 is an admirable number.

It is a Curzon number.

It is a plaindrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 55577778.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4631476 + ... + 4631487.

It is an arithmetic number, because the mean of its divisors is an integer number (13894446).

Almost surely, 2^55577778 is an apocalyptic number.

55577778 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.

55577778 is a wasteful number, since it uses less digits than its factorization.

55577778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9262968.

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

The square root of 55577778 is about 7455.0505028470. The cubic root of 55577778 is about 381.6222840996.

The spelling of 55577778 in words is "fifty-five million, five hundred seventy-seven thousand, seven hundred seventy-eight".