394243530505440 has 768 divisors, whose sum is σ = 1581724456058880. Its totient is φ = 80153401466880.

The previous prime is 394243530505421. The next prime is 394243530505477. The reversal of 394243530505440 is 44505035342493.

It is a super-2 number, since 2×394243530505440² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 6026036569 + ... + 6026101991.

It is an arithmetic number, because the mean of its divisors is an integer number (2059537052160).

Almost surely, 2^{394243530505440} is an apocalyptic number.

394243530505440 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 394243530505440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (790862228029440).

394243530505440 is an abundant number, since it is smaller than the sum of its proper divisors (1187480925553440).

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

394243530505440 is a wasteful number, since it uses less digits than its factorization.

394243530505440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 68975 (or 68967 counting only the distinct ones).

The product of its (nonzero) digits is 15552000, while the sum is 51.

The spelling of 394243530505440 in words is "three hundred ninety-four trillion, two hundred forty-three billion, five hundred thirty million, five hundred five thousand, four hundred forty".