399691395180 has 1728 divisors, whose sum is σ = 1748456865792. Its totient is φ = 71484456960.

The previous prime is 399691395121. The next prime is 399691395253. The reversal of 399691395180 is 81593196993.

It is a happy number.

399691395180 is a `hidden beast` number, since 3 + 9 + 9 + 69 + 1 + 395 + 180 = 666.

It is a super-2 number, since 2×399691395180² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 575 ways as a sum of consecutive naturals, for example, 3147176277 + ... + 3147176403.

It is an arithmetic number, because the mean of its divisors is an integer number (1011838464).

Almost surely, 2^399691395180 is an apocalyptic number.

399691395180 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 399691395180, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (874228432896).

399691395180 is an abundant number, since it is smaller than the sum of its proper divisors (1348765470612).

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

399691395180 is a wasteful number, since it uses less digits than its factorization.

399691395180 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 252 (or 228 counting only the distinct ones).

The product of its (nonzero) digits is 14171760, while the sum is 63.

The spelling of 399691395180 in words is "three hundred ninety-nine billion, six hundred ninety-one million, three hundred ninety-five thousand, one hundred eighty".