1956438889 has 2 divisors, whose sum is σ = 1956438890. Its totient is φ = 1956438888.

The previous prime is 1956438839. The next prime is 1956438893. The reversal of 1956438889 is 9888346591.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1296360025 + 660078864 = 36005^2 + 25692^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1956438889 is a prime.

It is not a weakly prime, because it can be changed into another prime (1956438839) 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, 978219444 + 978219445.

It is an arithmetic number, because the mean of its divisors is an integer number (978219445).

Almost surely, 2^1956438889 is an apocalyptic number.

It is an amenable number.

1956438889 is a deficient number, since it is larger than the sum of its proper divisors (1).

1956438889 is an equidigital number, since it uses as much as digits as its factorization.

1956438889 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 14929920, while the sum is 61.

The square root of 1956438889 is about 44231.6503083482. The cubic root of 1956438889 is about 1250.7065635258.

The spelling of 1956438889 in words is "one billion, nine hundred fifty-six million, four hundred thirty-eight thousand, eight hundred eighty-nine".