666520151 has 24 divisors (see below), whose sum is σ = 770421120. Its totient is φ = 575079120.

The previous prime is 666520123. The next prime is 666520163. The reversal of 666520151 is 151025666.

It is not a de Polignac number, because 666520151 - 2¹⁸ = 666258007 is a prime.

It is a super-2 number, since 2×666520151² = 888498223378125602, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666520121) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 385976 + ... + 387698.

It is an arithmetic number, because the mean of its divisors is an integer number (32100880).

Almost surely, 2^666520151 is an apocalyptic number.

666520151 is a deficient number, since it is larger than the sum of its proper divisors (103900969).

666520151 is a wasteful number, since it uses less digits than its factorization.

666520151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1907 (or 1896 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 32.

The square root of 666520151 is about 25817.0515551253. The cubic root of 666520151 is about 873.5164634354.

The spelling of 666520151 in words is "six hundred sixty-six million, five hundred twenty thousand, one hundred fifty-one".