390400055 has 8 divisors (see below), whose sum is σ = 468590832. Its totient is φ = 312246208.

The previous prime is 390400051. The next prime is 390400069. The reversal of 390400055 is 550004093.

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

It is a cyclic number.

It is not a de Polignac number, because 390400055 - 2² = 390400051 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 390399997 and 390400033.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (390400051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26867 + ... + 38763.

It is an arithmetic number, because the mean of its divisors is an integer number (58573854).

Almost surely, 2^390400055 is an apocalyptic number.

390400055 is a deficient number, since it is larger than the sum of its proper divisors (78190777).

390400055 is a wasteful number, since it uses less digits than its factorization.

390400055 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18465.

The product of its (nonzero) digits is 2700, while the sum is 26.

The square root of 390400055 is about 19758.5438481686. The cubic root of 390400055 is about 730.8640890671.

The spelling of 390400055 in words is "three hundred ninety million, four hundred thousand, fifty-five".