821697923241 has 36 divisors (see below), whose sum is σ = 1286919412428. Its totient is φ = 504991573632.

The previous prime is 821697923237. The next prime is 821697923279. The reversal of 821697923241 is 142329796128.

It can be written as a sum of positive squares in 6 ways, for example, as 145545302016 + 676152621225 = 381504^2 + 822285^2 .

It is not a de Polignac number, because 821697923241 - 2² = 821697923237 is a prime.

It is not an unprimeable number, because it can be changed into a prime (821697923141) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 794571 + ... + 1508223.

Almost surely, 2^821697923241 is an apocalyptic number.

It is an amenable number.

821697923241 is a deficient number, since it is larger than the sum of its proper divisors (465221489187).

821697923241 is a wasteful number, since it uses less digits than its factorization.

821697923241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 714442 (or 714426 counting only the distinct ones).

The product of its digits is 2612736, while the sum is 54.

The spelling of 821697923241 in words is "eight hundred twenty-one billion, six hundred ninety-seven million, nine hundred twenty-three thousand, two hundred forty-one".