405640660066 has 16 divisors (see below), whose sum is σ = 644270820480. Its totient is φ = 190884386880.

The previous prime is 405640660031. The next prime is 405640660069. The reversal of 405640660066 is 660066046504.

It is not an unprimeable number, because it can be changed into a prime (405640660069) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1239451 + ... + 1532161.

It is an arithmetic number, because the mean of its divisors is an integer number (40266926280).

Almost surely, 2^405640660066 is an apocalyptic number.

405640660066 is a deficient number, since it is larger than the sum of its proper divisors (238630160414).

405640660066 is a wasteful number, since it uses less digits than its factorization.

405640660066 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 333489.

The product of its (nonzero) digits is 622080, while the sum is 43.

The spelling of 405640660066 in words is "four hundred five billion, six hundred forty million, six hundred sixty thousand, sixty-six".