395407721 has 8 divisors (see below), whose sum is σ = 409561920. Its totient is φ = 381288208.

The previous prime is 395407717. The next prime is 395407723. The reversal of 395407721 is 127704593.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 395407721 - 2² = 395407717 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (395407723) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15740 + ... + 32226.

It is an arithmetic number, because the mean of its divisors is an integer number (51195240).

Almost surely, 2^395407721 is an apocalyptic number.

It is an amenable number.

395407721 is a deficient number, since it is larger than the sum of its proper divisors (14154199).

395407721 is a wasteful number, since it uses less digits than its factorization.

395407721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17343.

The product of its (nonzero) digits is 52920, while the sum is 38.

The square root of 395407721 is about 19884.8616037427. The cubic root of 395407721 is about 733.9757563138.

The spelling of 395407721 in words is "three hundred ninety-five million, four hundred seven thousand, seven hundred twenty-one".