394921001 has 2 divisors, whose sum is σ = 394921002. Its totient is φ = 394921000.

The previous prime is 394920991. The next prime is 394921003. The reversal of 394921001 is 100129493.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 369408400 + 25512601 = 19220^2 + 5051^2 .

It is a cyclic number.

It is not a de Polignac number, because 394921001 - 2¹⁰ = 394919977 is a prime.

Together with 394921003, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (394921003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 197460500 + 197460501.

It is an arithmetic number, because the mean of its divisors is an integer number (197460501).

Almost surely, 2^394921001 is an apocalyptic number.

It is an amenable number.

394921001 is a deficient number, since it is larger than the sum of its proper divisors (1).

394921001 is an equidigital number, since it uses as much as digits as its factorization.

394921001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 394921001 is about 19872.6193794376. The cubic root of 394921001 is about 733.6744745894.

The spelling of 394921001 in words is "three hundred ninety-four million, nine hundred twenty-one thousand, one".