31532161 has 4 divisors (see below), whose sum is σ = 33387012. Its totient is φ = 29677312.

The previous prime is 31532141. The next prime is 31532167. The reversal of 31532161 is 16123513.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16123513 = 7 ⋅2303359.

It can be written as a sum of positive squares in 2 ways, for example, as 20930625 + 10601536 = 4575^2 + 3256^2 .

It is a cyclic number.

It is not a de Polignac number, because 31532161 - 2⁹ = 31531649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31532167) 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, 927400 + ... + 927433.

It is an arithmetic number, because the mean of its divisors is an integer number (8346753).

Almost surely, 2^31532161 is an apocalyptic number.

It is an amenable number.

31532161 is a deficient number, since it is larger than the sum of its proper divisors (1854851).

31532161 is a wasteful number, since it uses less digits than its factorization.

31532161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1854850.

The product of its digits is 540, while the sum is 22.

The square root of 31532161 is about 5615.3504788214. The cubic root of 31532161 is about 315.9254250393.

Adding to 31532161 its reverse (16123513), we get a palindrome (47655674).

The spelling of 31532161 in words is "thirty-one million, five hundred thirty-two thousand, one hundred sixty-one".