1688999953 has 2 divisors, whose sum is σ = 1688999954. Its totient is φ = 1688999952.

The previous prime is 1688999947. The next prime is 1688999999. The reversal of 1688999953 is 3599998861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1405650064 + 283349889 = 37492^2 + 16833^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1688999953 is a prime.

It is not a weakly prime, because it can be changed into another prime (1680999953) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 844499976 + 844499977.

It is an arithmetic number, because the mean of its divisors is an integer number (844499977).

Almost surely, 2^1688999953 is an apocalyptic number.

It is an amenable number.

1688999953 is a deficient number, since it is larger than the sum of its proper divisors (1).

1688999953 is an equidigital number, since it uses as much as digits as its factorization.

1688999953 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 37791360, while the sum is 67.

The square root of 1688999953 is about 41097.4446042573. Note that the first 3 decimals coincide. The cubic root of 1688999953 is about 1190.9034292504.

The spelling of 1688999953 in words is "one billion, six hundred eighty-eight million, nine hundred ninety-nine thousand, nine hundred fifty-three".