31945129 has 4 divisors (see below), whose sum is σ = 31964884. Its totient is φ = 31925376.

The previous prime is 31945073. The next prime is 31945139. The reversal of 31945129 is 92154913.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 92154913 = 9041 ⋅10193.

It can be written as a sum of positive squares in 2 ways, for example, as 16160400 + 15784729 = 4020^2 + 3973^2 .

It is a cyclic number.

It is not a de Polignac number, because 31945129 - 2¹³ = 31936937 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31945094 and 31945103.

It is not an unprimeable number, because it can be changed into a prime (31945139) 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, 7212 + ... + 10765.

It is an arithmetic number, because the mean of its divisors is an integer number (7991221).

Almost surely, 2^31945129 is an apocalyptic number.

It is an amenable number.

31945129 is a deficient number, since it is larger than the sum of its proper divisors (19755).

31945129 is a wasteful number, since it uses less digits than its factorization.

31945129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19754.

The product of its digits is 9720, while the sum is 34.

The square root of 31945129 is about 5652.0022116061. The cubic root of 31945129 is about 317.2986434855.

The spelling of 31945129 in words is "thirty-one million, nine hundred forty-five thousand, one hundred twenty-nine".