31425161 has 4 divisors (see below), whose sum is σ = 31524612. Its totient is φ = 31325712.

The previous prime is 31425133. The next prime is 31425179. The reversal of 31425161 is 16152413.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5973136 + 25452025 = 2444^2 + 5045^2 .

It is a cyclic number.

It is not a de Polignac number, because 31425161 - 2¹⁸ = 31163017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (31425101) 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, 49250 + ... + 49883.

It is an arithmetic number, because the mean of its divisors is an integer number (7881153).

Almost surely, 2^31425161 is an apocalyptic number.

It is an amenable number.

31425161 is a deficient number, since it is larger than the sum of its proper divisors (99451).

31425161 is an equidigital number, since it uses as much as digits as its factorization.

31425161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99450.

The product of its digits is 720, while the sum is 23.

The square root of 31425161 is about 5605.8149273768. The cubic root of 31425161 is about 315.5676704161.

Adding to 31425161 its reverse (16152413), we get a palindrome (47577574).

The spelling of 31425161 in words is "thirty-one million, four hundred twenty-five thousand, one hundred sixty-one".