82236561921 has 12 divisors (see below), whose sum is σ = 118822172820. Its totient is φ = 54807746400.

The previous prime is 82236561917. The next prime is 82236561931. The reversal of 82236561921 is 12916563228.

82236561921 is a `hidden beast` number, since 8 + 2 + 2 + 3 + 6 + 5 + 619 + 21 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 57581281521 + 24655280400 = 239961^2 + 157020^2 .

It is not a de Polignac number, because 82236561921 - 2² = 82236561917 is a prime.

It is not an unprimeable number, because it can be changed into a prime (82236561931) 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, 1354326 + ... + 1413743.

It is an arithmetic number, because the mean of its divisors is an integer number (9901847735).

Almost surely, 2^82236561921 is an apocalyptic number.

It is an amenable number.

82236561921 is a deficient number, since it is larger than the sum of its proper divisors (36585610899).

82236561921 is a wasteful number, since it uses less digits than its factorization.

82236561921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2771376 (or 2771373 counting only the distinct ones).

The product of its digits is 311040, while the sum is 45.

The spelling of 82236561921 in words is "eighty-two billion, two hundred thirty-six million, five hundred sixty-one thousand, nine hundred twenty-one".