1685221964788 has 24 divisors (see below), whose sum is σ = 2978453638944. Its totient is φ = 834235860000.

The previous prime is 1685221964779. The next prime is 1685221964809. The reversal of 1685221964788 is 8874691225861.

It is a super-2 number, since 2×1685221964788² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12883531 + ... + 13013677.

It is an arithmetic number, because the mean of its divisors is an integer number (124102234956).

Almost surely, 2^{1685221964788} is an apocalyptic number.

It is an amenable number.

1685221964788 is a deficient number, since it is larger than the sum of its proper divisors (1293231674156).

1685221964788 is a wasteful number, since it uses less digits than its factorization.

1685221964788 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 162303 (or 162301 counting only the distinct ones).

The product of its digits is 92897280, while the sum is 67.

The spelling of 1685221964788 in words is "one trillion, six hundred eighty-five billion, two hundred twenty-one million, nine hundred sixty-four thousand, seven hundred eighty-eight".