31720124 has 6 divisors (see below), whose sum is σ = 55510224. Its totient is φ = 15860060.

The previous prime is 31720121. The next prime is 31720133. The reversal of 31720124 is 42102713.

It is a junction number, because it is equal to n+sod(n) for n = 31720096 and 31720105.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31720121) 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 as a sum of consecutive naturals, namely, 3965012 + ... + 3965019.

It is an arithmetic number, because the mean of its divisors is an integer number (9251704).

Almost surely, 2^31720124 is an apocalyptic number.

It is an amenable number.

31720124 is a deficient number, since it is larger than the sum of its proper divisors (23790100).

31720124 is a wasteful number, since it uses less digits than its factorization.

31720124 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7930035 (or 7930033 counting only the distinct ones).

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 31720124 is about 5632.0621445435. The cubic root of 31720124 is about 316.5519249420.

Adding to 31720124 its reverse (42102713), we get a palindrome (73822837).

The spelling of 31720124 in words is "thirty-one million, seven hundred twenty thousand, one hundred twenty-four".