1685961216 has 140 divisors (see below), whose sum is σ = 5051752002. Its totient is φ = 561862656.

The previous prime is 1685961191. The next prime is 1685961241. The reversal of 1685961216 is 6121695861.

1685961216 is a `hidden beast` number, since 16 + 8 + 5 + 9 + 612 + 16 = 666.

It is an interprime number because it is at equal distance from previous prime (1685961191) and next prime (1685961241).

It can be written as a sum of positive squares in only one way, i.e., 1684281600 + 1679616 = 41040^2 + 1296^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 370990 + ... + 375506.

Almost surely, 2^1685961216 is an apocalyptic number.

1685961216 is a gapful number since it is divisible by the number (16) 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 1685961216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2525876001).

1685961216 is an abundant number, since it is smaller than the sum of its proper divisors (3365790786).

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

1685961216 is an frugal number, since it uses more digits than its factorization.

1685961216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4553 (or 4522 counting only the distinct ones).

The product of its digits is 155520, while the sum is 45.

The square root of 1685961216 is about 41060.4580588186. The cubic root of 1685961216 is about 1190.1888022823.

The spelling of 1685961216 in words is "one billion, six hundred eighty-five million, nine hundred sixty-one thousand, two hundred sixteen".