501216101 has 4 divisors (see below), whose sum is σ = 501294732. Its totient is φ = 501137472.

The previous prime is 501216031. The next prime is 501216113. The reversal of 501216101 is 101612105.

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

It can be written as a sum of positive squares in 2 ways, for example, as 115132900 + 386083201 = 10730^2 + 19649^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-501216101 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 501216101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (501116101) 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, 28820 + ... + 42813.

It is an arithmetic number, because the mean of its divisors is an integer number (125323683).

Almost surely, 2^501216101 is an apocalyptic number.

It is an amenable number.

501216101 is a deficient number, since it is larger than the sum of its proper divisors (78631).

501216101 is an equidigital number, since it uses as much as digits as its factorization.

501216101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78630.

The product of its (nonzero) digits is 60, while the sum is 17.

The square root of 501216101 is about 22387.8561054872. The cubic root of 501216101 is about 794.3434849990.

Adding to 501216101 its reverse (101612105), we get a palindrome (602828206).

The spelling of 501216101 in words is "five hundred one million, two hundred sixteen thousand, one hundred one".