501273618161 has 4 divisors (see below), whose sum is σ = 501584390772. Its totient is φ = 500962845552.

The previous prime is 501273618143. The next prime is 501273618163. The reversal of 501273618161 is 161816372105.

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 213334058161 + 287939560000 = 461881^2 + 536600^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-501273618161 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (501273618163) 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, 155383886 + ... + 155387111.

It is an arithmetic number, because the mean of its divisors is an integer number (125396097693).

Almost surely, 2^501273618161 is an apocalyptic number.

It is an amenable number.

501273618161 is a deficient number, since it is larger than the sum of its proper divisors (310772611).

501273618161 is a wasteful number, since it uses less digits than its factorization.

501273618161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 310772610.

The product of its (nonzero) digits is 60480, while the sum is 41.

The spelling of 501273618161 in words is "five hundred one billion, two hundred seventy-three million, six hundred eighteen thousand, one hundred sixty-one".