1686620052 has 144 divisors (see below), whose sum is σ = 4697941248. Its totient is φ = 507064320.

The previous prime is 1686620041. The next prime is 1686620053. The reversal of 1686620052 is 2500266861.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1686619989 and 1686620016.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1686620053) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6412873 + ... + 6413135.

It is an arithmetic number, because the mean of its divisors is an integer number (32624592).

Almost surely, 2^1686620052 is an apocalyptic number.

1686620052 is a gapful number since it is divisible by the number (12) 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 1686620052, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2348970624).

1686620052 is an abundant number, since it is smaller than the sum of its proper divisors (3011321196).

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

1686620052 is a wasteful number, since it uses less digits than its factorization.

1686620052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 550 (or 545 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The square root of 1686620052 is about 41068.4800303103. The cubic root of 1686620052 is about 1190.3438151622.

The spelling of 1686620052 in words is "one billion, six hundred eighty-six million, six hundred twenty thousand, fifty-two".