390380645 has 4 divisors (see below), whose sum is σ = 468456780. Its totient is φ = 312304512.

The previous prime is 390380621. The next prime is 390380647. The reversal of 390380645 is 546083093.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 273373156 + 117007489 = 16534^2 + 10817^2 .

It is a cyclic number.

It is not a de Polignac number, because 390380645 - 2¹⁸ = 390118501 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 390380599 and 390380608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (390380647) 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, 39038060 + ... + 39038069.

It is an arithmetic number, because the mean of its divisors is an integer number (117114195).

Almost surely, 2^390380645 is an apocalyptic number.

It is an amenable number.

390380645 is a deficient number, since it is larger than the sum of its proper divisors (78076135).

390380645 is an equidigital number, since it uses as much as digits as its factorization.

390380645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78076134.

The product of its (nonzero) digits is 77760, while the sum is 38.

The square root of 390380645 is about 19758.0526621426. The cubic root of 390380645 is about 730.8519764432.

It can be divided in two parts, 3903 and 80645, that added together give a palindrome (84548).

The spelling of 390380645 in words is "three hundred ninety million, three hundred eighty thousand, six hundred forty-five".