31103661 has 4 divisors (see below), whose sum is σ = 41471552. Its totient is φ = 20735772.

The previous prime is 31103641. The next prime is 31103711. The reversal of 31103661 is 16630113.

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.

It is not a de Polignac number, because 31103661 - 2⁷ = 31103533 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31103641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5183941 + ... + 5183946.

It is an arithmetic number, because the mean of its divisors is an integer number (10367888).

Almost surely, 2^31103661 is an apocalyptic number.

It is an amenable number.

31103661 is a deficient number, since it is larger than the sum of its proper divisors (10367891).

31103661 is a wasteful number, since it uses less digits than its factorization.

31103661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10367890.

The product of its (nonzero) digits is 324, while the sum is 21.

The square root of 31103661 is about 5577.0656262949. The cubic root of 31103661 is about 314.4878247709.

Adding to 31103661 its reverse (16630113), we get a palindrome (47733774).

The spelling of 31103661 in words is "thirty-one million, one hundred three thousand, six hundred sixty-one".