66977792 has 72 divisors (see below), whose sum is σ = 155188656. Its totient is φ = 28311552.

The previous prime is 66977767. The next prime is 66977819. The reversal of 66977792 is 29777966.

It is a nialpdrome in base 2 and base 4.

It is a zygodrome in base 2.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 917468 + ... + 917540.

It is an arithmetic number, because the mean of its divisors is an integer number (2155398).

Almost surely, 2^66977792 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66977792, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (77594328).

66977792 is an abundant number, since it is smaller than the sum of its proper divisors (88210864).

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

66977792 is an frugal number, since it uses more digits than its factorization.

66977792 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 114 (or 82 counting only the distinct ones).

The product of its digits is 2000376, while the sum is 53.

The square root of 66977792 is about 8183.9960899306. The cubic root of 66977792 is about 406.1099300307.

The spelling of 66977792 in words is "sixty-six million, nine hundred seventy-seven thousand, seven hundred ninety-two".