131221042 has 4 divisors (see below), whose sum is σ = 196831566. Its totient is φ = 65610520.

The previous prime is 131221037. The next prime is 131221061. The reversal of 131221042 is 240122131.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 240122131 = 661 ⋅363271.

It can be written as a sum of positive squares in only one way, i.e., 93876721 + 37344321 = 9689^2 + 6111^2 .

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 32805259 + ... + 32805262.

Almost surely, 2^131221042 is an apocalyptic number.

131221042 is a deficient number, since it is larger than the sum of its proper divisors (65610524).

131221042 is an equidigital number, since it uses as much as digits as its factorization.

131221042 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65610523.

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 131221042 is about 11455.1753369383. The cubic root of 131221042 is about 508.1608006670.

Adding to 131221042 its reverse (240122131), we get a palindrome (371343173).

The spelling of 131221042 in words is "one hundred thirty-one million, two hundred twenty-one thousand, forty-two".