666888051 has 32 divisors (see below), whose sum is σ = 927520000. Its totient is φ = 425969280.

The previous prime is 666888017. The next prime is 666888071. The reversal of 666888051 is 150888666.

It is a happy number.

It is not a de Polignac number, because 666888051 - 2⁶ = 666887987 is a prime.

It is a super-4 number, since 4×666888051⁴ (a number of 36 digits) contains 4444 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666888071) 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, 1336200 + ... + 1336698.

It is an arithmetic number, because the mean of its divisors is an integer number (28985000).

Almost surely, 2^666888051 is an apocalyptic number.

666888051 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

666888051 is a deficient number, since it is larger than the sum of its proper divisors (260631949).

666888051 is a wasteful number, since it uses less digits than its factorization.

666888051 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 739.

The product of its (nonzero) digits is 552960, while the sum is 48.

The square root of 666888051 is about 25824.1757080454. The cubic root of 666888051 is about 873.6771525489.

The spelling of 666888051 in words is "six hundred sixty-six million, eight hundred eighty-eight thousand, fifty-one".