31206157 has 2 divisors, whose sum is σ = 31206158. Its totient is φ = 31206156.

The previous prime is 31206143. The next prime is 31206173. The reversal of 31206157 is 75160213.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30184036 + 1022121 = 5494^2 + 1011^2 .

It is a cyclic number.

It is not a de Polignac number, because 31206157 - 2¹¹ = 31204109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31206137) 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, 15603078 + 15603079.

It is an arithmetic number, because the mean of its divisors is an integer number (15603079).

Almost surely, 2^31206157 is an apocalyptic number.

It is an amenable number.

31206157 is a deficient number, since it is larger than the sum of its proper divisors (1).

31206157 is an equidigital number, since it uses as much as digits as its factorization.

31206157 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1260, while the sum is 25.

The square root of 31206157 is about 5586.2471302297. The cubic root of 31206157 is about 314.8328902828.

The spelling of 31206157 in words is "thirty-one million, two hundred six thousand, one hundred fifty-seven".