31554161 has 2 divisors, whose sum is σ = 31554162. Its totient is φ = 31554160.

The previous prime is 31554143. The next prime is 31554163. The reversal of 31554161 is 16145513.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16654561 + 14899600 = 4081^2 + 3860^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31554161 is a prime.

It is a Sophie Germain prime.

Together with 31554163, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 31554161.

It is not a weakly prime, because it can be changed into another prime (31554163) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15777080 + 15777081.

It is an arithmetic number, because the mean of its divisors is an integer number (15777081).

Almost surely, 2^31554161 is an apocalyptic number.

It is an amenable number.

31554161 is a deficient number, since it is larger than the sum of its proper divisors (1).

31554161 is an equidigital number, since it uses as much as digits as its factorization.

31554161 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1800, while the sum is 26.

The square root of 31554161 is about 5617.3090532745. The cubic root of 31554161 is about 315.9988817191.

Adding to 31554161 its reverse (16145513), we get a palindrome (47699674).

The spelling of 31554161 in words is "thirty-one million, five hundred fifty-four thousand, one hundred sixty-one".