31980061 has 2 divisors, whose sum is σ = 31980062. Its totient is φ = 31980060.

The previous prime is 31980049. The next prime is 31980083. The reversal of 31980061 is 16008913.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 30525625 + 1454436 = 5525^2 + 1206^2 .

It is a cyclic number.

It is not a de Polignac number, because 31980061 - 2⁵ = 31980029 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (31980001) by changing a digit.

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 as a sum of consecutive naturals, namely, 15990030 + 15990031.

It is an arithmetic number, because the mean of its divisors is an integer number (15990031).

Almost surely, 2^31980061 is an apocalyptic number.

It is an amenable number.

31980061 is a deficient number, since it is larger than the sum of its proper divisors (1).

31980061 is an equidigital number, since it uses as much as digits as its factorization.

31980061 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1296, while the sum is 28.

The square root of 31980061 is about 5655.0915996118. The cubic root of 31980061 is about 317.4142567150.

Adding to 31980061 its reverse (16008913), we get a palindrome (47988974).

The spelling of 31980061 in words is "thirty-one million, nine hundred eighty thousand, sixty-one".