31661617 has 8 divisors (see below), whose sum is σ = 34741224. Its totient is φ = 28674048.

The previous prime is 31661611. The next prime is 31661681. The reversal of 31661617 is 71616613.

It can be written as a sum of positive squares in 4 ways, for example, as 1290496 + 30371121 = 1136^2 + 5511^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-31661617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31661611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 22288 + ... + 23665.

It is an arithmetic number, because the mean of its divisors is an integer number (4342653).

Almost surely, 2^31661617 is an apocalyptic number.

It is an amenable number.

31661617 is a deficient number, since it is larger than the sum of its proper divisors (3079607).

31661617 is a wasteful number, since it uses less digits than its factorization.

31661617 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46019.

The product of its digits is 4536, while the sum is 31.

The square root of 31661617 is about 5626.8656461657. The cubic root of 31661617 is about 316.3571810414.

The spelling of 31661617 in words is "thirty-one million, six hundred sixty-one thousand, six hundred seventeen".