686415630431220 has 192 divisors, whose sum is σ = 1947451598486016. Its totient is φ = 180628502446080.

The previous prime is 686415630431213. The next prime is 686415630431221. The reversal of 686415630431220 is 22134036514686.

It is a super-2 number, since 2×686415630431220² (a number of 30 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (686415630431221) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2950140609 + ... + 2950373271.

It is an arithmetic number, because the mean of its divisors is an integer number (10142977075448).

Almost surely, 2^{686415630431220} is an apocalyptic number.

686415630431220 is a gapful number since it is divisible by the number (60) 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 686415630431220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (973725799243008).

686415630431220 is an abundant number, since it is smaller than the sum of its proper divisors (1261035968054796).

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

686415630431220 is a wasteful number, since it uses less digits than its factorization.

686415630431220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 234250 (or 234248 counting only the distinct ones).

The product of its (nonzero) digits is 4976640, while the sum is 51.

The spelling of 686415630431220 in words is "six hundred eighty-six trillion, four hundred fifteen billion, six hundred thirty million, four hundred thirty-one thousand, two hundred twenty".