66139790 has 8 divisors (see below), whose sum is σ = 119051640. Its totient is φ = 26455912.

The previous prime is 66139781. The next prime is 66139823. The reversal of 66139790 is 9793166.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3306980 + ... + 3306999.

It is an arithmetic number, because the mean of its divisors is an integer number (14881455).

Almost surely, 2^66139790 is an apocalyptic number.

66139790 is a deficient number, since it is larger than the sum of its proper divisors (52911850).

66139790 is a wasteful number, since it uses less digits than its factorization.

66139790 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6613986.

The product of its (nonzero) digits is 61236, while the sum is 41.

The square root of 66139790 is about 8132.6373336083. The cubic root of 66139790 is about 404.4091164907.

The spelling of 66139790 in words is "sixty-six million, one hundred thirty-nine thousand, seven hundred ninety".