31720104 has 48 divisors (see below), whose sum is σ = 92519700. Its totient is φ = 9759744.

The previous prime is 31720103. The next prime is 31720121. The reversal of 31720104 is 40102713.

It can be written as a sum of positive squares in 2 ways, for example, as 31472100 + 248004 = 5610^2 + 498^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (31720103) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 16009 + ... + 17880.

Almost surely, 2^31720104 is an apocalyptic number.

It is an amenable number.

31720104 is an abundant number, since it is smaller than the sum of its proper divisors (60799596).

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

31720104 is a wasteful number, since it uses less digits than its factorization.

31720104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33914 (or 33907 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 18.

The square root of 31720104 is about 5632.0603689946. The cubic root of 31720104 is about 316.5518584118.

Adding to 31720104 its reverse (40102713), we get a palindrome (71822817).

The spelling of 31720104 in words is "thirty-one million, seven hundred twenty thousand, one hundred four".