1912168421 has 2 divisors, whose sum is σ = 1912168422. Its totient is φ = 1912168420.

The previous prime is 1912168387. The next prime is 1912168429. The reversal of 1912168421 is 1248612191.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1892685025 + 19483396 = 43505^2 + 4414^2 .

It is an emirp because it is prime and its reverse (1248612191) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1912168421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1912168429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 956084210 + 956084211.

It is an arithmetic number, because the mean of its divisors is an integer number (956084211).

Almost surely, 2^1912168421 is an apocalyptic number.

It is an amenable number.

1912168421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1912168421 is an equidigital number, since it uses as much as digits as its factorization.

1912168421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6912, while the sum is 35.

The square root of 1912168421 is about 43728.3480250512. The cubic root of 1912168421 is about 1241.2008011000.

It can be divided in two parts, 191 and 2168421, that added together give a palindrome (2168612).

The spelling of 1912168421 in words is "one billion, nine hundred twelve million, one hundred sixty-eight thousand, four hundred twenty-one".