666263776 has 48 divisors (see below), whose sum is σ = 1351682640. Its totient is φ = 323077120.

The previous prime is 666263753. The next prime is 666263783. The reversal of 666263776 is 677362666.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 233430 + ... + 236266.

It is an arithmetic number, because the mean of its divisors is an integer number (28160055).

Almost surely, 2^666263776 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 666263776, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (675841320).

666263776 is an abundant number, since it is smaller than the sum of its proper divisors (685418864).

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

666263776 is a wasteful number, since it uses less digits than its factorization.

666263776 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3067 (or 3059 counting only the distinct ones).

The product of its digits is 2286144, while the sum is 49.

The square root of 666263776 is about 25812.0858513991. The cubic root of 666263776 is about 873.4044505664.

The spelling of 666263776 in words is "six hundred sixty-six million, two hundred sixty-three thousand, seven hundred seventy-six".