1919912857 has 2 divisors, whose sum is σ = 1919912858. Its totient is φ = 1919912856.

The previous prime is 1919912851. The next prime is 1919912861. The reversal of 1919912857 is 7582199191.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1834922896 + 84989961 = 42836^2 + 9219^2 .

It is a cyclic number.

It is not a de Polignac number, because 1919912857 - 2¹⁵ = 1919880089 is a prime.

It is not a weakly prime, because it can be changed into another prime (1919912851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 959956428 + 959956429.

It is an arithmetic number, because the mean of its divisors is an integer number (959956429).

Almost surely, 2^1919912857 is an apocalyptic number.

It is an amenable number.

1919912857 is a deficient number, since it is larger than the sum of its proper divisors (1).

1919912857 is an equidigital number, since it uses as much as digits as its factorization.

1919912857 is an evil number, because the sum of its binary digits is even.

The product of its digits is 408240, while the sum is 52.

The square root of 1919912857 is about 43816.8102102378. The cubic root of 1919912857 is about 1242.8741983775.

The spelling of 1919912857 in words is "one billion, nine hundred nineteen million, nine hundred twelve thousand, eight hundred fifty-seven".