394506840 has 288 divisors, whose sum is σ = 1494553680. Its totient is φ = 83026944.

The previous prime is 394506821. The next prime is 394506841. The reversal of 394506840 is 48605493.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (394506841) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 993522 + ... + 993918.

Almost surely, 2^394506840 is an apocalyptic number.

394506840 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 394506840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (747276840).

394506840 is an abundant number, since it is smaller than the sum of its proper divisors (1100046840).

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

394506840 is a wasteful number, since it uses less digits than its factorization.

394506840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 451 (or 427 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 39.

The square root of 394506840 is about 19862.1962531841. The cubic root of 394506840 is about 733.4179121915.

The spelling of 394506840 in words is "three hundred ninety-four million, five hundred six thousand, eight hundred forty".