1994778287 has 2 divisors, whose sum is σ = 1994778288. Its totient is φ = 1994778286.

The previous prime is 1994778241. The next prime is 1994778301. The reversal of 1994778287 is 7828774991.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1994778287 - 2¹⁴ = 1994761903 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1994738287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 997389143 + 997389144.

It is an arithmetic number, because the mean of its divisors is an integer number (997389144).

Almost surely, 2^1994778287 is an apocalyptic number.

1994778287 is a deficient number, since it is larger than the sum of its proper divisors (1).

1994778287 is an equidigital number, since it uses as much as digits as its factorization.

1994778287 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 14224896, while the sum is 62.

The square root of 1994778287 is about 44662.9408682411. The cubic root of 1994778287 is about 1258.8236032272.

The spelling of 1994778287 in words is "one billion, nine hundred ninety-four million, seven hundred seventy-eight thousand, two hundred eighty-seven".