1642955779 has 2 divisors, whose sum is σ = 1642955780. Its totient is φ = 1642955778.

The previous prime is 1642955777. The next prime is 1642955819. The reversal of 1642955779 is 9775592461.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1642955779 - 2¹ = 1642955777 is a prime.

Together with 1642955777, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (1642955771) 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, 821477889 + 821477890.

It is an arithmetic number, because the mean of its divisors is an integer number (821477890).

Almost surely, 2^1642955779 is an apocalyptic number.

1642955779 is a deficient number, since it is larger than the sum of its proper divisors (1).

1642955779 is an equidigital number, since it uses as much as digits as its factorization.

1642955779 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4762800, while the sum is 55.

The square root of 1642955779 is about 40533.3909141587. The cubic root of 1642955779 is about 1179.9817528060.

The spelling of 1642955779 in words is "one billion, six hundred forty-two million, nine hundred fifty-five thousand, seven hundred seventy-nine".