66131242 has 4 divisors (see below), whose sum is σ = 99196866. Its totient is φ = 33065620.

The previous prime is 66131239. The next prime is 66131249. The reversal of 66131242 is 24213166.

66131242 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24213166 = 2 ⋅12106583.

It can be written as a sum of positive squares in only one way, i.e., 63345681 + 2785561 = 7959^2 + 1669^2 .

It is not an unprimeable number, because it can be changed into a prime (66131249) 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 as a sum of consecutive naturals, namely, 16532809 + ... + 16532812.

Almost surely, 2^66131242 is an apocalyptic number.

66131242 is a deficient number, since it is larger than the sum of its proper divisors (33065624).

66131242 is a wasteful number, since it uses less digits than its factorization.

66131242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33065623.

The product of its digits is 1728, while the sum is 25.

The square root of 66131242 is about 8132.1117798515. Note that the first 3 decimals coincide. The cubic root of 66131242 is about 404.3916936047.

The spelling of 66131242 in words is "sixty-six million, one hundred thirty-one thousand, two hundred forty-two".