31103121 has 16 divisors (see below), whose sum is σ = 47484800. Its totient is φ = 17739648.

The previous prime is 31103119. The next prime is 31103129. The reversal of 31103121 is 12130113.

It is not a de Polignac number, because 31103121 - 2¹ = 31103119 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31103097 and 31103106.

It is not an unprimeable number, because it can be changed into a prime (31103129) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13845 + ... + 15933.

It is an arithmetic number, because the mean of its divisors is an integer number (2967800).

Almost surely, 2^31103121 is an apocalyptic number.

It is an amenable number.

31103121 is a deficient number, since it is larger than the sum of its proper divisors (16381679).

31103121 is a wasteful number, since it uses less digits than its factorization.

31103121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2808.

The product of its (nonzero) digits is 18, while the sum is 12.

The square root of 31103121 is about 5577.0172135291. The cubic root of 31103121 is about 314.4860047879.

Adding to 31103121 its reverse (12130113), we get a palindrome (43233234).

The spelling of 31103121 in words is "thirty-one million, one hundred three thousand, one hundred twenty-one".