390815040 has 448 divisors, whose sum is σ = 1643286528. Its totient is φ = 76185600.

The previous prime is 390814987. The next prime is 390815069. The reversal of 390815040 is 40518093.

It is a tau number, because it is divible by the number of its divisors (448).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 390814989 and 390815007.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1256485 + ... + 1256795.

Almost surely, 2^390815040 is an apocalyptic number.

390815040 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 390815040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (821643264).

390815040 is an abundant number, since it is smaller than the sum of its proper divisors (1252471488).

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

390815040 is a wasteful number, since it uses less digits than its factorization.

390815040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 366 (or 356 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 390815040 is about 19769.0424654306. The cubic root of 390815040 is about 731.1229604715.

The spelling of 390815040 in words is "three hundred ninety million, eight hundred fifteen thousand, forty".