820116540 has 36 divisors (see below), whose sum is σ = 2487687384. Its totient is φ = 218697696.

The previous prime is 820116523. The next prime is 820116547. The reversal of 820116540 is 45611028.

820116540 is a `hidden beast` number, since 8 + 2 + 0 + 1 + 1 + 654 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×820116540² = 1345182278363143200, which contains 22 as substring.

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (820116547) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2277922 + ... + 2278281.

Almost surely, 2^820116540 is an apocalyptic number.

It is an amenable number.

820116540 is an abundant number, since it is smaller than the sum of its proper divisors (1667570844).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

820116540 is a wasteful number, since it uses less digits than its factorization.

820116540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4556218 (or 4556213 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 27.

The square root of 820116540 is about 28637.6769309244. The cubic root of 820116540 is about 936.0345017964.

Adding to 820116540 its reverse (45611028), we get a palindrome (865727568).

The spelling of 820116540 in words is "eight hundred twenty million, one hundred sixteen thousand, five hundred forty".