66999830 has 16 divisors (see below), whose sum is σ = 121052880. Its totient is φ = 26699232.

The previous prime is 66999797. The next prime is 66999853. The reversal of 66999830 is 3899966.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9764 + ... + 15143.

It is an arithmetic number, because the mean of its divisors is an integer number (7565805).

Almost surely, 2^66999830 is an apocalyptic number.

66999830 is a deficient number, since it is larger than the sum of its proper divisors (54053050).

66999830 is a wasteful number, since it uses less digits than its factorization.

66999830 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25183.

The product of its (nonzero) digits is 629856, while the sum is 50.

The square root of 66999830 is about 8185.3423874631. The cubic root of 66999830 is about 406.1544665303.

The spelling of 66999830 in words is "sixty-six million, nine hundred ninety-nine thousand, eight hundred thirty".