66299405 has 8 divisors (see below), whose sum is σ = 84239352. Its totient is φ = 49919488.

The previous prime is 66299399. The next prime is 66299459. The reversal of 66299405 is 50499266.

It can be written as a sum of positive squares in 4 ways, for example, as 25989604 + 40309801 = 5098^2 + 6349^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 66299405 - 2¹² = 66295309 is a prime.

It is a super-2 number, since 2×66299405² = 8791222206708050, which contains 22 as substring.

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, 389912 + ... + 390081.

It is an arithmetic number, because the mean of its divisors is an integer number (10529919).

Almost surely, 2^66299405 is an apocalyptic number.

It is an amenable number.

66299405 is a deficient number, since it is larger than the sum of its proper divisors (17939947).

66299405 is a wasteful number, since it uses less digits than its factorization.

66299405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 780015.

The product of its (nonzero) digits is 116640, while the sum is 41.

The square root of 66299405 is about 8142.4446574723. Note that the first 3 decimals coincide. The cubic root of 66299405 is about 404.7341750004.

The spelling of 66299405 in words is "sixty-six million, two hundred ninety-nine thousand, four hundred five".