385640640 has 672 divisors, whose sum is σ = 1734580224. Its totient is φ = 76308480.

The previous prime is 385640617. The next prime is 385640657. The reversal of 385640640 is 46046583.

385640640 is a `hidden beast` number, since 3 + 8 + 5 + 6 + 4 + 0 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (672).

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 = 385640595 and 385640604.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 8205097 + ... + 8205143.

Almost surely, 2^385640640 is an apocalyptic number.

385640640 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 385640640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (867290112).

385640640 is an abundant number, since it is smaller than the sum of its proper divisors (1348939584).

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

385640640 is a wasteful number, since it uses less digits than its factorization.

385640640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 125 (or 112 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The square root of 385640640 is about 19637.7351036213. The cubic root of 385640640 is about 727.8819194228.

The spelling of 385640640 in words is "three hundred eighty-five million, six hundred forty thousand, six hundred forty".