31500061 has 16 divisors (see below), whose sum is σ = 34583040. Its totient is φ = 28607040.

The previous prime is 31500047. The next prime is 31500083. The reversal of 31500061 is 16000513.

It is a cyclic number.

It is not a de Polignac number, because 31500061 - 2⁷ = 31499933 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 (31500361) 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 15 ways as a sum of consecutive naturals, for example, 32790 + ... + 33736.

It is an arithmetic number, because the mean of its divisors is an integer number (2161440).

Almost surely, 2^31500061 is an apocalyptic number.

31500061 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

It is an amenable number.

31500061 is a deficient number, since it is larger than the sum of its proper divisors (3082979).

31500061 is a wasteful number, since it uses less digits than its factorization.

31500061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1044.

The product of its (nonzero) digits is 90, while the sum is 16.

The square root of 31500061 is about 5612.4915144702. The cubic root of 31500061 is about 315.8181837440.

Adding to 31500061 its reverse (16000513), we get a palindrome (47500574).

The spelling of 31500061 in words is "thirty-one million, five hundred thousand, sixty-one".