66861792 has 72 divisors (see below), whose sum is σ = 196297920. Its totient is φ = 21565440.

The previous prime is 66861787. The next prime is 66861797. The reversal of 66861792 is 29716866.

It is an interprime number because it is at equal distance from previous prime (66861787) and next prime (66861797).

It is a tau number, because it is divible by the number of its divisors (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66861797) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5184 + ... + 12672.

It is an arithmetic number, because the mean of its divisors is an integer number (2726360).

Almost surely, 2^66861792 is an apocalyptic number.

66861792 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66861792, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98148960).

66861792 is an abundant number, since it is smaller than the sum of its proper divisors (129436128).

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

66861792 is a wasteful number, since it uses less digits than its factorization.

66861792 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7536 (or 7525 counting only the distinct ones).

The product of its digits is 217728, while the sum is 45.

The square root of 66861792 is about 8176.9060163365. The cubic root of 66861792 is about 405.8753449400.

The spelling of 66861792 in words is "sixty-six million, eight hundred sixty-one thousand, seven hundred ninety-two".