131022221 has 4 divisors (see below), whose sum is σ = 142933344. Its totient is φ = 119111100.

The previous prime is 131022187. The next prime is 131022259. The reversal of 131022221 is 122220131.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 122220131 = 11 ⋅11110921.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-131022221 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 131022196 and 131022205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (131022821) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5955545 + ... + 5955566.

It is an arithmetic number, because the mean of its divisors is an integer number (35733336).

Almost surely, 2^131022221 is an apocalyptic number.

131022221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

131022221 is a deficient number, since it is larger than the sum of its proper divisors (11911123).

131022221 is a wasteful number, since it uses less digits than its factorization.

131022221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11911122.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 131022221 is about 11446.4938299900. The cubic root of 131022221 is about 507.9040224676.

Adding to 131022221 its reverse (122220131), we get a palindrome (253242352).

The spelling of 131022221 in words is "one hundred thirty-one million, twenty-two thousand, two hundred twenty-one".