1656651671 has 2 divisors, whose sum is σ = 1656651672. Its totient is φ = 1656651670.

The previous prime is 1656651631. The next prime is 1656651673. The reversal of 1656651671 is 1761566561.

It is a strong prime.

It is an emirp because it is prime and its reverse (1761566561) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1656651671 is a prime.

Together with 1656651673, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1656651673) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 828325835 + 828325836.

It is an arithmetic number, because the mean of its divisors is an integer number (828325836).

Almost surely, 2^1656651671 is an apocalyptic number.

1656651671 is a deficient number, since it is larger than the sum of its proper divisors (1).

1656651671 is an equidigital number, since it uses as much as digits as its factorization.

1656651671 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 226800, while the sum is 44.

The square root of 1656651671 is about 40701.9860817626. The cubic root of 1656651671 is about 1183.2515107259.

The spelling of 1656651671 in words is "one billion, six hundred fifty-six million, six hundred fifty-one thousand, six hundred seventy-one".