394001009 has 2 divisors, whose sum is σ = 394001010. Its totient is φ = 394001008.

The previous prime is 394000987. The next prime is 394001039. The reversal of 394001009 is 900100493.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 289000000 + 105001009 = 17000^2 + 10247^2 .

It is a cyclic number.

It is not a de Polignac number, because 394001009 - 2¹⁶ = 393935473 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (394001039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 197000504 + 197000505.

It is an arithmetic number, because the mean of its divisors is an integer number (197000505).

Almost surely, 2^394001009 is an apocalyptic number.

It is an amenable number.

394001009 is a deficient number, since it is larger than the sum of its proper divisors (1).

394001009 is an equidigital number, since it uses as much as digits as its factorization.

394001009 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 394001009 is about 19849.4586576058. The cubic root of 394001009 is about 733.1043188231.

The spelling of 394001009 in words is "three hundred ninety-four million, one thousand, nine".