31606121 has 4 divisors (see below), whose sum is σ = 32377044. Its totient is φ = 30835200.

The previous prime is 31606097. The next prime is 31606181. The reversal of 31606121 is 12160613.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12160613 = 197 ⋅61729.

It can be written as a sum of positive squares in 2 ways, for example, as 648025 + 30958096 = 805^2 + 5564^2 .

It is a cyclic number.

It is not a de Polignac number, because 31606121 - 2¹⁰ = 31605097 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 31606093 and 31606102.

It is not an unprimeable number, because it can be changed into a prime (31606181) 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, 385400 + ... + 385481.

It is an arithmetic number, because the mean of its divisors is an integer number (8094261).

Almost surely, 2^31606121 is an apocalyptic number.

It is an amenable number.

31606121 is a deficient number, since it is larger than the sum of its proper divisors (770923).

31606121 is an equidigital number, since it uses as much as digits as its factorization.

31606121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 770922.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 31606121 is about 5621.9321411771. The cubic root of 31606121 is about 316.1722375945.

Adding to 31606121 its reverse (12160613), we get a palindrome (43766734).

It can be divided in two parts, 3160612 and 1, that added together give a palindrome (3160613).

The spelling of 31606121 in words is "thirty-one million, six hundred six thousand, one hundred twenty-one".