1690856473 has 2 divisors, whose sum is σ = 1690856474. Its totient is φ = 1690856472.

The previous prime is 1690856471. The next prime is 1690856491. The reversal of 1690856473 is 3746580961.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1435879449 + 254977024 = 37893^2 + 15968^2 .

It is a cyclic number.

It is not a de Polignac number, because 1690856473 - 2¹ = 1690856471 is a prime.

It is a super-2 number, since 2×1690856473² = 5717991224571999458, which contains 22 as substring.

Together with 1690856471, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1690856471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 845428236 + 845428237.

It is an arithmetic number, because the mean of its divisors is an integer number (845428237).

Almost surely, 2^1690856473 is an apocalyptic number.

It is an amenable number.

1690856473 is a deficient number, since it is larger than the sum of its proper divisors (1).

1690856473 is an equidigital number, since it uses as much as digits as its factorization.

1690856473 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1088640, while the sum is 49.

The square root of 1690856473 is about 41120.0252067043. The cubic root of 1690856473 is about 1191.3396097350.

The spelling of 1690856473 in words is "one billion, six hundred ninety million, eight hundred fifty-six thousand, four hundred seventy-three".