509401666 has 8 divisors (see below), whose sum is σ = 804318480. Its totient is φ = 241295508.

The previous prime is 509401663. The next prime is 509401679. The reversal of 509401666 is 666104905.

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

It is not an unprimeable number, because it can be changed into a prime (509401661) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6702616 + ... + 6702691.

It is an arithmetic number, because the mean of its divisors is an integer number (100539810).

Almost surely, 2^509401666 is an apocalyptic number.

509401666 is a deficient number, since it is larger than the sum of its proper divisors (294916814).

509401666 is a wasteful number, since it uses less digits than its factorization.

509401666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13405328.

The product of its (nonzero) digits is 38880, while the sum is 37.

The square root of 509401666 is about 22569.9283561114. The cubic root of 509401666 is about 798.6444052928.

The spelling of 509401666 in words is "five hundred nine million, four hundred one thousand, six hundred sixty-six".