390404020 has 48 divisors (see below), whose sum is σ = 886354560. Its totient is φ = 143938944.

The previous prime is 390403999. The next prime is 390404023. The reversal of 390404020 is 20404093.

390404020 = 168² + 169² + ... + 1055².

It is a junction number, because it is equal to n+sod(n) for n = 390403982 and 390404000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (390404023) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 177 + ... + 27943.

It is an arithmetic number, because the mean of its divisors is an integer number (18465720).

Almost surely, 2^390404020 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 390404020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (443177280).

390404020 is an abundant number, since it is smaller than the sum of its proper divisors (495950540).

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

390404020 is a wasteful number, since it uses less digits than its factorization.

390404020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27832 (or 27830 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 22.

The square root of 390404020 is about 19758.6441842552. The cubic root of 390404020 is about 730.8665633378.

The spelling of 390404020 in words is "three hundred ninety million, four hundred four thousand, twenty".