31677521 has 2 divisors, whose sum is σ = 31677522. Its totient is φ = 31677520.

The previous prime is 31677487. The next prime is 31677553. The reversal of 31677521 is 12577613.

It is an a-pointer prime, because the next prime (31677553) can be obtained adding 31677521 to its sum of digits (32).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 30647296 + 1030225 = 5536^2 + 1015^2 .

It is an emirp because it is prime and its reverse (12577613) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31677521 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (31677221) 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 as a sum of consecutive naturals, namely, 15838760 + 15838761.

It is an arithmetic number, because the mean of its divisors is an integer number (15838761).

Almost surely, 2^31677521 is an apocalyptic number.

It is an amenable number.

31677521 is a deficient number, since it is larger than the sum of its proper divisors (1).

31677521 is an equidigital number, since it uses as much as digits as its factorization.

31677521 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8820, while the sum is 32.

The square root of 31677521 is about 5628.2786889066. The cubic root of 31677521 is about 316.4101421437.

The spelling of 31677521 in words is "thirty-one million, six hundred seventy-seven thousand, five hundred twenty-one".