66451242 has 64 divisors (see below), whose sum is σ = 160030080. Its totient is φ = 18124800.

The previous prime is 66451219. The next prime is 66451247. The reversal of 66451242 is 24215466.

It is not an unprimeable number, because it can be changed into a prime (66451247) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 34234 + ... + 36122.

It is an arithmetic number, because the mean of its divisors is an integer number (2500470).

Almost surely, 2^66451242 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66451242, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (80015040).

66451242 is an abundant number, since it is smaller than the sum of its proper divisors (93578838).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66451242 is a wasteful number, since it uses less digits than its factorization.

66451242 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1959.

The product of its digits is 11520, while the sum is 30.

The square root of 66451242 is about 8151.7631221718. The cubic root of 66451242 is about 405.0429096435.

It can be divided in two parts, 6645 and 1242, that added together give a palindrome (7887).

The spelling of 66451242 in words is "sixty-six million, four hundred fifty-one thousand, two hundred forty-two".