66811490 has 16 divisors (see below), whose sum is σ = 120373560. Its totient is φ = 26699520.

The previous prime is 66811471. The next prime is 66811517. The reversal of 66811490 is 9411866.

It can be written as a sum of positive squares in 4 ways, for example, as 61199329 + 5612161 = 7823^2 + 2369^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 66811490.

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 7 ways as a sum of consecutive naturals, for example, 11156 + ... + 16064.

Almost surely, 2^66811490 is an apocalyptic number.

66811490 is a deficient number, since it is larger than the sum of its proper divisors (53562070).

66811490 is a wasteful number, since it uses less digits than its factorization.

66811490 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6277.

The product of its (nonzero) digits is 10368, while the sum is 35.

The square root of 66811490 is about 8173.8295798236. The cubic root of 66811490 is about 405.7735356053.

The spelling of 66811490 in words is "sixty-six million, eight hundred eleven thousand, four hundred ninety".