997238131 has 4 divisors (see below), whose sum is σ = 997335592. Its totient is φ = 997140672.

The previous prime is 997238113. The next prime is 997238149. The reversal of 997238131 is 131832799.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 131832799 = 7 ⋅18833257.

It is an interprime number because it is at equal distance from previous prime (997238113) and next prime (997238149).

It is a cyclic number.

It is not a de Polignac number, because 997238131 - 2¹³ = 997229939 is a prime.

It is a super-2 number, since 2×997238131² = 1988967779840746322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (997238191) 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 3 ways as a sum of consecutive naturals, for example, 31305 + ... + 54538.

It is an arithmetic number, because the mean of its divisors is an integer number (249333898).

Almost surely, 2^997238131 is an apocalyptic number.

997238131 is a deficient number, since it is larger than the sum of its proper divisors (97461).

997238131 is a wasteful number, since it uses less digits than its factorization.

997238131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97460.

The product of its digits is 81648, while the sum is 43.

The square root of 997238131 is about 31579.0774247760. The cubic root of 997238131 is about 999.0785281504.

The spelling of 997238131 in words is "nine hundred ninety-seven million, two hundred thirty-eight thousand, one hundred thirty-one".