399686400000000 has 1620 divisors, whose sum is σ = 1502545375227624. Its totient is φ = 106168320000000.

The previous prime is 399686399999993. The next prime is 399686400000071. The reversal of 399686400000000 is 4686993.

It is a tau number, because it is divible by the number of its divisors (1620).

It is a super-3 number, since 3×399686400000000³ (a number of 45 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a junction number, because it is equal to n+sod(n) for n = 399686399999892 and 399686399999901.

It is an unprimeable number.

It is a polite number, since it can be written in 107 ways as a sum of consecutive naturals, for example, 1555199999872 + ... + 1555200000128.

Almost surely, 2^{399686400000000} is an apocalyptic number.

399686400000000 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 399686400000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (751272687613812).

399686400000000 is an abundant number, since it is smaller than the sum of its proper divisors (1102858975227624).

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

399686400000000 is an frugal number, since it uses more digits than its factorization.

399686400000000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 340 (or 267 counting only the distinct ones).

The product of its (nonzero) digits is 279936, while the sum is 45.

Adding to 399686400000000 its reverse (4686993), we get a palindrome (399686404686993).

The spelling of 399686400000000 in words is "three hundred ninety-nine trillion, six hundred eighty-six billion, four hundred million", and thus it is an aban number.