66828361 has 8 divisors (see below), whose sum is σ = 68051880. Its totient is φ = 65613312.

The previous prime is 66828353. The next prime is 66828371. The reversal of 66828361 is 16382866.

66828361 = 5780² + 5781².

It can be written as a sum of positive squares in 4 ways, for example, as 308025 + 66520336 = 555^2 + 8156^2 .

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 66828361 - 2³ = 66828353 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66828331) 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, 15045 + ... + 18973.

It is an arithmetic number, because the mean of its divisors is an integer number (8506485).

Almost surely, 2^66828361 is an apocalyptic number.

66828361 is the 5781-st centered square number.

It is an amenable number.

66828361 is a deficient number, since it is larger than the sum of its proper divisors (1223519).

66828361 is a wasteful number, since it uses less digits than its factorization.

66828361 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4235.

The product of its digits is 82944, while the sum is 40.

The square root of 66828361 is about 8174.8615278792. The cubic root of 66828361 is about 405.8076875612.

The spelling of 66828361 in words is "sixty-six million, eight hundred twenty-eight thousand, three hundred sixty-one".