397726641 has 12 divisors (see below), whose sum is σ = 618686068. Its totient is φ = 244754784.

The previous prime is 397726631. The next prime is 397726657. The reversal of 397726641 is 146627793.

It can be written as a sum of positive squares in 2 ways, for example, as 210830400 + 186896241 = 14520^2 + 13671^2 .

It is not a de Polignac number, because 397726641 - 2⁹ = 397726129 is a prime.

It is a super-2 number, since 2×397726641² = 316372961922285762, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (397726631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1699570 + ... + 1699803.

Almost surely, 2^397726641 is an apocalyptic number.

It is an amenable number.

397726641 is a deficient number, since it is larger than the sum of its proper divisors (220959427).

397726641 is a wasteful number, since it uses less digits than its factorization.

397726641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3399392 (or 3399389 counting only the distinct ones).

The product of its digits is 381024, while the sum is 45.

The square root of 397726641 is about 19943.0850421894. The cubic root of 397726641 is about 735.4077925878.

The spelling of 397726641 in words is "three hundred ninety-seven million, seven hundred twenty-six thousand, six hundred forty-one".