66143990 has 16 divisors (see below), whose sum is σ = 129882960. Its totient is φ = 24052320.

The previous prime is 66143989. The next prime is 66144017. The reversal of 66143990 is 9934166.

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, 300545 + ... + 300764.

It is an arithmetic number, because the mean of its divisors is an integer number (8117685).

Almost surely, 2^66143990 is an apocalyptic number.

66143990 is a deficient number, since it is larger than the sum of its proper divisors (63738970).

66143990 is a wasteful number, since it uses less digits than its factorization.

66143990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 601327.

The product of its (nonzero) digits is 34992, while the sum is 38.

The square root of 66143990 is about 8132.8955483272. The cubic root of 66143990 is about 404.4176765539.

The spelling of 66143990 in words is "sixty-six million, one hundred forty-three thousand, nine hundred ninety".