31123201 has 4 divisors (see below), whose sum is σ = 31425472. Its totient is φ = 30820932.

The previous prime is 31123199. The next prime is 31123217. The reversal of 31123201 is 10232113.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 10232113 = 17 ⋅601889.

It is a cyclic number.

It is not a de Polignac number, because 31123201 - 2¹ = 31123199 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31123241) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 150981 + ... + 151186.

It is an arithmetic number, because the mean of its divisors is an integer number (7856368).

Almost surely, 2^31123201 is an apocalyptic number.

It is an amenable number.

31123201 is a deficient number, since it is larger than the sum of its proper divisors (302271).

31123201 is a wasteful number, since it uses less digits than its factorization.

31123201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 302270.

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 31123201 is about 5578.8171685403. The cubic root of 31123201 is about 314.5536670278.

Adding to 31123201 its reverse (10232113), we get a palindrome (41355314).

The spelling of 31123201 in words is "thirty-one million, one hundred twenty-three thousand, two hundred one".