1642955819 has 2 divisors, whose sum is σ = 1642955820. Its totient is φ = 1642955818.

The previous prime is 1642955779. The next prime is 1642955917. The reversal of 1642955819 is 9185592461.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1642955819 is a prime.

It is a super-2 number, since 2×1642955819² = 5398607646371921522, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (1642957819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 821477909 + 821477910.

It is an arithmetic number, because the mean of its divisors is an integer number (821477910).

Almost surely, 2^1642955819 is an apocalyptic number.

1642955819 is a deficient number, since it is larger than the sum of its proper divisors (1).

1642955819 is an equidigital number, since it uses as much as digits as its factorization.

1642955819 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 777600, while the sum is 50.

The square root of 1642955819 is about 40533.3914075790. The cubic root of 1642955819 is about 1179.9817623821.

The spelling of 1642955819 in words is "one billion, six hundred forty-two million, nine hundred fifty-five thousand, eight hundred nineteen".