666450025 has 6 divisors (see below), whose sum is σ = 826398062. Its totient is φ = 533160000.

The previous prime is 666450013. The next prime is 666450053. The reversal of 666450025 is 520054666.

It can be written as a sum of positive squares in 3 ways, for example, as 8219689 + 658230336 = 2867^2 + 25656^2 .

It is not a de Polignac number, because 666450025 - 2¹³ = 666441833 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 13328976 + ... + 13329025.

Almost surely, 2^666450025 is an apocalyptic number.

It is an amenable number.

666450025 is a deficient number, since it is larger than the sum of its proper divisors (159948037).

666450025 is a wasteful number, since it uses less digits than its factorization.

666450025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26658011 (or 26658006 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 34.

The square root of 666450025 is about 25815.6933860007. The cubic root of 666450025 is about 873.4858275205.

The spelling of 666450025 in words is "six hundred sixty-six million, four hundred fifty thousand, twenty-five".