394006489920 has 336 divisors, whose sum is σ = 1466985453120. Its totient is φ = 99537693696.

The previous prime is 394006489871. The next prime is 394006489927. The reversal of 394006489920 is 29984600493.

394006489920 is a `hidden beast` number, since 39 + 40 + 0 + 6 + 489 + 92 + 0 = 666.

It is a super-2 number, since 2×394006489920² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (394006489927) 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, 3055879 + ... + 3182201.

Almost surely, 2^394006489920 is an apocalyptic number.

394006489920 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 394006489920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (733492726560).

394006489920 is an abundant number, since it is smaller than the sum of its proper divisors (1072978963200).

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

394006489920 is a wasteful number, since it uses less digits than its factorization.

394006489920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126387 (or 126352 counting only the distinct ones).

The product of its (nonzero) digits is 3359232, while the sum is 54.

The spelling of 394006489920 in words is "three hundred ninety-four billion, six million, four hundred eighty-nine thousand, nine hundred twenty".