132991981 has 2 divisors, whose sum is σ = 132991982. Its totient is φ = 132991980.

The previous prime is 132991967. The next prime is 132991993. The reversal of 132991981 is 189199231.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 74545956 + 58446025 = 8634^2 + 7645^2 .

It is a cyclic number.

It is not a de Polignac number, because 132991981 - 2⁷ = 132991853 is a prime.

It is a super-2 number, since 2×132991981² = 35373734020608722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (132991381) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 66495990 + 66495991.

It is an arithmetic number, because the mean of its divisors is an integer number (66495991).

Almost surely, 2^132991981 is an apocalyptic number.

It is an amenable number.

132991981 is a deficient number, since it is larger than the sum of its proper divisors (1).

132991981 is an equidigital number, since it uses as much as digits as its factorization.

132991981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34992, while the sum is 43.

The square root of 132991981 is about 11532.2149216879. The cubic root of 132991981 is about 510.4366131632.

The spelling of 132991981 in words is "one hundred thirty-two million, nine hundred ninety-one thousand, nine hundred eighty-one".