390716640 has 288 divisors, whose sum is σ = 1426553856. Its totient is φ = 97152000.

The previous prime is 390716603. The next prime is 390716647. The reversal of 390716640 is 46617093.

390716640 is a `hidden beast` number, since 3 + 9 + 0 + 7 + 1 + 6 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (288).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 390716595 and 390716604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (390716647) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1556515 + ... + 1556765.

It is an arithmetic number, because the mean of its divisors is an integer number (4953312).

Almost surely, 2^390716640 is an apocalyptic number.

390716640 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 390716640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (713276928).

390716640 is an abundant number, since it is smaller than the sum of its proper divisors (1035837216).

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

390716640 is a wasteful number, since it uses less digits than its factorization.

390716640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 342 (or 331 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 36.

The square root of 390716640 is about 19766.5535690975. The cubic root of 390716640 is about 731.0615942405.

The spelling of 390716640 in words is "three hundred ninety million, seven hundred sixteen thousand, six hundred forty".