399924001 has 2 divisors, whose sum is σ = 399924002. Its totient is φ = 399924000.

The previous prime is 399923999. The next prime is 399924017. The reversal of 399924001 is 100429993.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 235469025 + 164454976 = 15345^2 + 12824^2 .

It is a cyclic number.

It is not a de Polignac number, because 399924001 - 2¹ = 399923999 is a prime.

Together with 399923999, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (399954001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199962000 + 199962001.

It is an arithmetic number, because the mean of its divisors is an integer number (199962001).

Almost surely, 2^399924001 is an apocalyptic number.

It is an amenable number.

399924001 is a deficient number, since it is larger than the sum of its proper divisors (1).

399924001 is an equidigital number, since it uses as much as digits as its factorization.

399924001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17496, while the sum is 37.

The square root of 399924001 is about 19998.0999347438. The cubic root of 399924001 is about 736.7596329875.

The spelling of 399924001 in words is "three hundred ninety-nine million, nine hundred twenty-four thousand, one".