66490155 has 12 divisors (see below), whose sum is σ = 115249680. Its totient is φ = 35461392.

The previous prime is 66490103. The next prime is 66490159. The reversal of 66490155 is 55109466.

66490155 is a `hidden beast` number, since 6 + 649 + 0 + 1 + 5 + 5 = 666.

It is not a de Polignac number, because 66490155 - 2⁷ = 66490027 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66490159) 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 11 ways as a sum of consecutive naturals, for example, 738735 + ... + 738824.

It is an arithmetic number, because the mean of its divisors is an integer number (9604140).

Almost surely, 2^66490155 is an apocalyptic number.

66490155 is a deficient number, since it is larger than the sum of its proper divisors (48759525).

66490155 is a wasteful number, since it uses less digits than its factorization.

66490155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1477570 (or 1477567 counting only the distinct ones).

The product of its (nonzero) digits is 32400, while the sum is 36.

The square root of 66490155 is about 8154.1495571273. The cubic root of 66490155 is about 405.1219568702.

The spelling of 66490155 in words is "sixty-six million, four hundred ninety thousand, one hundred fifty-five".