131 can be written using four 4's:
See also 113
131 has 2
divisors, whose sum is σ = 132
Its totient is φ = 130
The previous prime is 127. The next prime is 137.
131 is nontrivially palindromic in base 10.
131 is an esthetic number in base 12, because in such base its adjacent digits differ by 1.
It is a weak prime.
It is a palprime.
It is a cyclic number.
It is not a de Polignac number, because 131 - 22 = 127 is a prime.
It is a super-2 number, since 2×1312 = 34322, which contains 22 as substring.
It is a Sophie Germain prime.
It is a Chen prime.
It is an Ulam number.
131 is an undulating number in base 10.
It is equal to p32 and since 131 and 32 have the same sum of digits, it is a Honaker prime.
It is a plaindrome in base 6, base 7, base 9, base 12 and base 15.
It is a nialpdrome in base 13, base 14 and base 16.
It is a pernicious number, because its binary representation contains a prime number (3) of ones.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 65 + 66.
It is an arithmetic number, because the mean of its divisors is an integer number (66).
131 is a deficient number, since it is larger than the sum of its proper divisors (1).
131 is an equidigital number, since it uses as much as digits as its factorization.
131 is an odious number, because the sum of its binary digits is odd.
The product of its digits is 3, while the sum is 5.
The square root of 131 is about 11.4455231423.
The cubic root of 131 is about 5.0787530781.
It can be divided in two parts, 1 and 31, that added together give a 5-th power (32 = 25).
The spelling of 131 in words is "one hundred thirty-one", and thus it is an aban number.