388639009440 has 864 divisors, whose sum is σ = 1514472313536. Its totient is φ = 90744192000.

The previous prime is 388639009393. The next prime is 388639009453. The reversal of 388639009440 is 44900936883.

It is a happy number.

388639009440 is a `hidden beast` number, since 38 + 86 + 3 + 90 + 0 + 9 + 440 = 666.

It is a super-2 number, since 2×388639009440² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 1841890935 + ... + 1841891145.

It is an arithmetic number, because the mean of its divisors is an integer number (1752861474).

Almost surely, 2^388639009440 is an apocalyptic number.

388639009440 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 388639009440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (757236156768).

388639009440 is an abundant number, since it is smaller than the sum of its proper divisors (1125833304096).

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

388639009440 is a wasteful number, since it uses less digits than its factorization.

388639009440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 327 (or 263 counting only the distinct ones).

The product of its (nonzero) digits is 4478976, while the sum is 54.

The spelling of 388639009440 in words is "three hundred eighty-eight billion, six hundred thirty-nine million, nine thousand, four hundred forty".