31129830 has 24 divisors (see below), whose sum is σ = 80937792. Its totient is φ = 8301264.

The previous prime is 31129829. The next prime is 31129841. The reversal of 31129830 is 3892113.

It is a junction number, because it is equal to n+sod(n) for n = 31129794 and 31129803.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 172854 + ... + 173033.

It is an arithmetic number, because the mean of its divisors is an integer number (3372408).

Almost surely, 2^31129830 is an apocalyptic number.

31129830 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

31129830 is an abundant number, since it is smaller than the sum of its proper divisors (49807962).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

31129830 is a wasteful number, since it uses less digits than its factorization.

31129830 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 345900 (or 345897 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 31129830 is about 5579.4112592638. The cubic root of 31129830 is about 314.5759979382.

The spelling of 31129830 in words is "thirty-one million, one hundred twenty-nine thousand, eight hundred thirty".