31085121 has 32 divisors (see below), whose sum is σ = 46126080. Its totient is φ = 18532800.

The previous prime is 31085111. The next prime is 31085123. The reversal of 31085121 is 12158013.

It is not a de Polignac number, because 31085121 - 2¹⁸ = 30822977 is a prime.

It is not an unprimeable number, because it can be changed into a prime (31085123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 171651 + ... + 171831.

It is an arithmetic number, because the mean of its divisors is an integer number (1441440).

Almost surely, 2^31085121 is an apocalyptic number.

It is an amenable number.

31085121 is a deficient number, since it is larger than the sum of its proper divisors (15040959).

31085121 is a wasteful number, since it uses less digits than its factorization.

31085121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 357.

The product of its (nonzero) digits is 240, while the sum is 21.

The square root of 31085121 is about 5575.4032141182. The cubic root of 31085121 is about 314.4253266281.

The spelling of 31085121 in words is "thirty-one million, eighty-five thousand, one hundred twenty-one".