1681613685 has 48 divisors (see below), whose sum is σ = 2990617344. Its totient is φ = 873645696.

The previous prime is 1681613669. The next prime is 1681613699. The reversal of 1681613685 is 5863161861.

It is not a de Polignac number, because 1681613685 - 2⁴ = 1681613669 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 1681613685.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 894967 + ... + 896843.

It is an arithmetic number, because the mean of its divisors is an integer number (62304528).

Almost surely, 2^1681613685 is an apocalyptic number.

1681613685 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1681613685 is a deficient number, since it is larger than the sum of its proper divisors (1309003659).

1681613685 is a wasteful number, since it uses less digits than its factorization.

1681613685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2394 (or 2391 counting only the distinct ones).

The product of its digits is 207360, while the sum is 45.

The square root of 1681613685 is about 41007.4832804941. The cubic root of 1681613685 is about 1189.1648885023.

The spelling of 1681613685 in words is "one billion, six hundred eighty-one million, six hundred thirteen thousand, six hundred eighty-five".