1685001681 has 24 divisors (see below), whose sum is σ = 2794902240. Its totient is φ = 967464000.

The previous prime is 1685001677. The next prime is 1685001701. The reversal of 1685001681 is 1861005861.

1685001681 is a `hidden beast` number, since 1 + 68 + 500 + 16 + 81 = 666.

It is not a de Polignac number, because 1685001681 - 2² = 1685001677 is a prime.

It is a super-2 number, since 2×1685001681² = 5678461329945651522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1685001611) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 446020 + ... + 449781.

It is an arithmetic number, because the mean of its divisors is an integer number (116454260).

Almost surely, 2^1685001681 is an apocalyptic number.

1685001681 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1685001681 is a deficient number, since it is larger than the sum of its proper divisors (1109900559).

1685001681 is a wasteful number, since it uses less digits than its factorization.

1685001681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 895837 (or 895834 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 36.

The square root of 1685001681 is about 41048.7719791957. The cubic root of 1685001681 is about 1189.9629677999.

The spelling of 1685001681 in words is "one billion, six hundred eighty-five million, one thousand, six hundred eighty-one".