31980138 has 8 divisors (see below), whose sum is σ = 63960288. Its totient is φ = 10660044.

The previous prime is 31980121. The next prime is 31980167. The reversal of 31980138 is 83108913.

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

31980138 is an admirable number.

It is a junction number, because it is equal to n+sod(n) for n = 31980099 and 31980108.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2665006 + ... + 2665017.

It is an arithmetic number, because the mean of its divisors is an integer number (7995036).

Almost surely, 2^31980138 is an apocalyptic number.

31980138 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

31980138 is a wasteful number, since it uses less digits than its factorization.

31980138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5330028.

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 31980138 is about 5655.0984076318. The cubic root of 31980138 is about 317.4145114662.

The spelling of 31980138 in words is "thirty-one million, nine hundred eighty thousand, one hundred thirty-eight".