1656106681 has 2 divisors, whose sum is σ = 1656106682. Its totient is φ = 1656106680.

The previous prime is 1656106619. The next prime is 1656106691. The reversal of 1656106681 is 1866016561.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1236225600 + 419881081 = 35160^2 + 20491^2 .

It is a cyclic number.

It is not a de Polignac number, because 1656106681 - 2¹³ = 1656098489 is a prime.

It is a super-2 number, since 2×1656106681² = 5485378677705671522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1656106691) by changing a digit.

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 as a sum of consecutive naturals, namely, 828053340 + 828053341.

It is an arithmetic number, because the mean of its divisors is an integer number (828053341).

Almost surely, 2^1656106681 is an apocalyptic number.

It is an amenable number.

1656106681 is a deficient number, since it is larger than the sum of its proper divisors (1).

1656106681 is an equidigital number, since it uses as much as digits as its factorization.

1656106681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 51840, while the sum is 40.

The square root of 1656106681 is about 40695.2906489191. The cubic root of 1656106681 is about 1183.1217447691.

The spelling of 1656106681 in words is "one billion, six hundred fifty-six million, one hundred six thousand, six hundred eighty-one".