1688922397 has 2 divisors, whose sum is σ = 1688922398. Its totient is φ = 1688922396.

The previous prime is 1688922359. The next prime is 1688922401. The reversal of 1688922397 is 7932298861.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1030024836 + 658897561 = 32094^2 + 25669^2 .

It is an emirp because it is prime and its reverse (7932298861) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1688922397 - 2¹¹ = 1688920349 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1688922337) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 844461198 + 844461199.

It is an arithmetic number, because the mean of its divisors is an integer number (844461199).

Almost surely, 2^1688922397 is an apocalyptic number.

It is an amenable number.

1688922397 is a deficient number, since it is larger than the sum of its proper divisors (1).

1688922397 is an equidigital number, since it uses as much as digits as its factorization.

1688922397 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2612736, while the sum is 55.

The square root of 1688922397 is about 41096.5010311097. The cubic root of 1688922397 is about 1190.8852008859.

The spelling of 1688922397 in words is "one billion, six hundred eighty-eight million, nine hundred twenty-two thousand, three hundred ninety-seven".