397987718 has 16 divisors (see below), whose sum is σ = 628795440. Its totient is φ = 188402400.

The previous prime is 397987717. The next prime is 397987721. The reversal of 397987718 is 817789793.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (397987717) 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 7 ways as a sum of consecutive naturals, for example, 102248 + ... + 106068.

It is an arithmetic number, because the mean of its divisors is an integer number (39299715).

Almost surely, 2^397987718 is an apocalyptic number.

397987718 is a gapful number since it is divisible by the number (38) formed by its first and last digit.

397987718 is a deficient number, since it is larger than the sum of its proper divisors (230807722).

397987718 is a wasteful number, since it uses less digits than its factorization.

397987718 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6583.

The product of its digits is 5334336, while the sum is 59.

The square root of 397987718 is about 19949.6295203695. The cubic root of 397987718 is about 735.5686703072.

The spelling of 397987718 in words is "three hundred ninety-seven million, nine hundred eighty-seven thousand, seven hundred eighteen".