31004561 has 8 divisors (see below), whose sum is σ = 37298880. Its totient is φ = 25176528.

The previous prime is 31004543. The next prime is 31004563. The reversal of 31004561 is 16540013.

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

It is a cyclic number.

It is not a de Polignac number, because 31004561 - 2⁶ = 31004497 is a prime.

It is a super-2 number, since 2×31004561² = 1922565605605442, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31004563) 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, 116426 + ... + 116691.

It is an arithmetic number, because the mean of its divisors is an integer number (4662360).

Almost surely, 2^31004561 is an apocalyptic number.

It is an amenable number.

31004561 is a deficient number, since it is larger than the sum of its proper divisors (6294319).

31004561 is a wasteful number, since it uses less digits than its factorization.

31004561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 233143.

The product of its (nonzero) digits is 360, while the sum is 20.

The square root of 31004561 is about 5568.1739376568. The cubic root of 31004561 is about 314.1534707601.

Adding to 31004561 its reverse (16540013), we get a palindrome (47544574).

The spelling of 31004561 in words is "thirty-one million, four thousand, five hundred sixty-one".