66765406 has 4 divisors (see below), whose sum is σ = 100148112. Its totient is φ = 33382702.

The previous prime is 66765401. The next prime is 66765407. The reversal of 66765406 is 60456766.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66765401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16691350 + ... + 16691353.

It is an arithmetic number, because the mean of its divisors is an integer number (25037028).

Almost surely, 2^66765406 is an apocalyptic number.

66765406 is a deficient number, since it is larger than the sum of its proper divisors (33382706).

66765406 is a wasteful number, since it uses less digits than its factorization.

66765406 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33382705.

The product of its (nonzero) digits is 181440, while the sum is 40.

The square root of 66765406 is about 8171.0100966772. The cubic root of 66765406 is about 405.6802184793.

The spelling of 66765406 in words is "sixty-six million, seven hundred sixty-five thousand, four hundred six".