31249109 has 2 divisors, whose sum is σ = 31249110. Its totient is φ = 31249108.

The previous prime is 31249103. The next prime is 31249139. The reversal of 31249109 is 90194213.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18447025 + 12802084 = 4295^2 + 3578^2 .

It is a cyclic number.

It is not a de Polignac number, because 31249109 - 2¹² = 31245013 is a prime.

It is equal to p_1930349 and since 31249109 and 1930349 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31249103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15624554 + 15624555.

It is an arithmetic number, because the mean of its divisors is an integer number (15624555).

Almost surely, 2^31249109 is an apocalyptic number.

It is an amenable number.

31249109 is a deficient number, since it is larger than the sum of its proper divisors (1).

31249109 is an equidigital number, since it uses as much as digits as its factorization.

31249109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 31249109 is about 5590.0902497187. The cubic root of 31249109 is about 314.9772688729.

The spelling of 31249109 in words is "thirty-one million, two hundred forty-nine thousand, one hundred nine".