31123018 has 8 divisors (see below), whose sum is σ = 47823300. Its totient is φ = 15181920.

The previous prime is 31123009. The next prime is 31123019. The reversal of 31123018 is 81032113.

It can be written as a sum of positive squares in 2 ways, for example, as 24137569 + 6985449 = 4913^2 + 2643^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 31122986 and 31123004.

It is not an unprimeable number, because it can be changed into a prime (31123019) 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, 189693 + ... + 189856.

Almost surely, 2^31123018 is an apocalyptic number.

31123018 is a deficient number, since it is larger than the sum of its proper divisors (16700282).

31123018 is a wasteful number, since it uses less digits than its factorization.

31123018 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 379592.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 31123018 is about 5578.8007671900. The cubic root of 31123018 is about 314.5530505164.

The spelling of 31123018 in words is "thirty-one million, one hundred twenty-three thousand, eighteen".