66723426 has 96 divisors (see below), whose sum is σ = 187020288. Its totient is φ = 17321040.

The previous prime is 66723413. The next prime is 66723431. The reversal of 66723426 is 62432766.

It is a happy number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 36531 + ... + 38313.

It is an arithmetic number, because the mean of its divisors is an integer number (1948128).

Almost surely, 2^66723426 is an apocalyptic number.

66723426 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 66723426, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93510144).

66723426 is an abundant number, since it is smaller than the sum of its proper divisors (120296862).

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

66723426 is a wasteful number, since it uses less digits than its factorization.

66723426 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1818 (or 1806 counting only the distinct ones).

The product of its digits is 72576, while the sum is 36.

The square root of 66723426 is about 8168.4408549000. The cubic root of 66723426 is about 405.5951743062.

The spelling of 66723426 in words is "sixty-six million, seven hundred twenty-three thousand, four hundred twenty-six".