397991038 has 4 divisors (see below), whose sum is σ = 596986560. Its totient is φ = 198995518.

The previous prime is 397990993. The next prime is 397991039. The reversal of 397991038 is 830199793.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 830199793 = 131 ⋅6337403.

It is a junction number, because it is equal to n+sod(n) for n = 397990982 and 397991000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (397991039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 99497758 + ... + 99497761.

It is an arithmetic number, because the mean of its divisors is an integer number (149246640).

Almost surely, 2^397991038 is an apocalyptic number.

397991038 is a deficient number, since it is larger than the sum of its proper divisors (198995522).

397991038 is a wasteful number, since it uses less digits than its factorization.

397991038 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 198995521.

The product of its (nonzero) digits is 367416, while the sum is 49.

The square root of 397991038 is about 19949.7127297613. The cubic root of 397991038 is about 735.5707156645.

The spelling of 397991038 in words is "three hundred ninety-seven million, nine hundred ninety-one thousand, thirty-eight".