397825717 has 4 divisors (see below), whose sum is σ = 397881280. Its totient is φ = 397770156.

The previous prime is 397825663. The next prime is 397825763. The reversal of 397825717 is 717528793.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 717528793 = 1471 ⋅487783.

It is a cyclic number.

It is not a de Polignac number, because 397825717 - 2²⁷ = 263607989 is a prime.

It is a super-2 number, since 2×397825717² = 316530602213128178, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (397829717) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15117 + ... + 32002.

It is an arithmetic number, because the mean of its divisors is an integer number (99470320).

Almost surely, 2^397825717 is an apocalyptic number.

It is an amenable number.

397825717 is a deficient number, since it is larger than the sum of its proper divisors (55563).

397825717 is an equidigital number, since it uses as much as digits as its factorization.

397825717 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55562.

The product of its digits is 740880, while the sum is 49.

The square root of 397825717 is about 19945.5688562648. The cubic root of 397825717 is about 735.4688522920.

The spelling of 397825717 in words is "three hundred ninety-seven million, eight hundred twenty-five thousand, seven hundred seventeen".