31530129 has 4 divisors (see below), whose sum is σ = 42040176. Its totient is φ = 21020084.

The previous prime is 31530097. The next prime is 31530143. The reversal of 31530129 is 92103513.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 92103513 = 3 ⋅30701171.

It is a cyclic number.

It is not a de Polignac number, because 31530129 - 2⁵ = 31530097 is a prime.

It is a super-3 number, since 3×31530129³ (a number of 23 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 31530099 and 31530108.

It is not an unprimeable number, because it can be changed into a prime (31530029) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5255019 + ... + 5255024.

It is an arithmetic number, because the mean of its divisors is an integer number (10510044).

Almost surely, 2^31530129 is an apocalyptic number.

It is an amenable number.

31530129 is a deficient number, since it is larger than the sum of its proper divisors (10510047).

31530129 is a wasteful number, since it uses less digits than its factorization.

31530129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10510046.

The product of its (nonzero) digits is 810, while the sum is 24.

The square root of 31530129 is about 5615.1695432997. The cubic root of 31530129 is about 315.9186385898.

The spelling of 31530129 in words is "thirty-one million, five hundred thirty thousand, one hundred twenty-nine".