820910489961 has 32 divisors (see below), whose sum is σ = 1129517593600. Its totient is φ = 530017992000.

The previous prime is 820910489951. The next prime is 820910489977. The reversal of 820910489961 is 169984019028.

It is a de Polignac number, because none of the positive numbers 2^k-820910489961 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (820910489951) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10499190 + ... + 10577088.

It is an arithmetic number, because the mean of its divisors is an integer number (35297424800).

Almost surely, 2^820910489961 is an apocalyptic number.

It is an amenable number.

820910489961 is a deficient number, since it is larger than the sum of its proper divisors (308607103639).

820910489961 is a wasteful number, since it uses less digits than its factorization.

820910489961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 78637.

The product of its (nonzero) digits is 2239488, while the sum is 57.

The spelling of 820910489961 in words is "eight hundred twenty billion, nine hundred ten million, four hundred eighty-nine thousand, nine hundred sixty-one".