1994243387 has 2 divisors, whose sum is σ = 1994243388. Its totient is φ = 1994243386.

The previous prime is 1994243371. The next prime is 1994243393. The reversal of 1994243387 is 7833424991.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1994243387 - 2⁴ = 1994243371 is a prime.

It is not a weakly prime, because it can be changed into another prime (1994243357) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 997121693 + 997121694.

It is an arithmetic number, because the mean of its divisors is an integer number (997121694).

Almost surely, 2^1994243387 is an apocalyptic number.

1994243387 is a deficient number, since it is larger than the sum of its proper divisors (1).

1994243387 is an equidigital number, since it uses as much as digits as its factorization.

1994243387 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1306368, while the sum is 50.

The square root of 1994243387 is about 44656.9522806920. The cubic root of 1994243387 is about 1258.7110752762.

The spelling of 1994243387 in words is "one billion, nine hundred ninety-four million, two hundred forty-three thousand, three hundred eighty-seven".