131221123 has 4 divisors (see below), whose sum is σ = 143150328. Its totient is φ = 119291920.

The previous prime is 131221121. The next prime is 131221151. The reversal of 131221123 is 321122131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 321122131 = 11 ⋅29192921.

It is not a de Polignac number, because 131221123 - 2¹ = 131221121 is a prime.

It is a super-2 number, since 2×131221123² = 34437966242762258, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 131221097 and 131221106.

It is not an unprimeable number, because it can be changed into a prime (131221121) 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 3 ways as a sum of consecutive naturals, for example, 5964586 + ... + 5964607.

It is an arithmetic number, because the mean of its divisors is an integer number (35787582).

Almost surely, 2^131221123 is an apocalyptic number.

131221123 is a deficient number, since it is larger than the sum of its proper divisors (11929205).

131221123 is a wasteful number, since it uses less digits than its factorization.

131221123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11929204.

The product of its digits is 72, while the sum is 16.

The square root of 131221123 is about 11455.1788724576. The cubic root of 131221123 is about 508.1609052260.

Adding to 131221123 its reverse (321122131), we get a palindrome (452343254).

The spelling of 131221123 in words is "one hundred thirty-one million, two hundred twenty-one thousand, one hundred twenty-three".