666451525 has 12 divisors (see below), whose sum is σ = 830732544. Its totient is φ = 530366000.

The previous prime is 666451507. The next prime is 666451553. The reversal of 666451525 is 525154666.

It is not a de Polignac number, because 666451525 - 2²⁵ = 632897093 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 65011 + ... + 74560.

It is an arithmetic number, because the mean of its divisors is an integer number (69227712).

Almost surely, 2^666451525 is an apocalyptic number.

It is an amenable number.

666451525 is a deficient number, since it is larger than the sum of its proper divisors (164281019).

666451525 is a wasteful number, since it uses less digits than its factorization.

666451525 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139772 (or 139767 counting only the distinct ones).

The product of its digits is 216000, while the sum is 40.

The square root of 666451525 is about 25815.7224380802. The cubic root of 666451525 is about 873.4864828473.

The spelling of 666451525 in words is "six hundred sixty-six million, four hundred fifty-one thousand, five hundred twenty-five".