202085721891 has 12 divisors (see below), whose sum is σ = 291906039568. Its totient is φ = 134721764784.

The previous prime is 202085721857. The next prime is 202085721923. The reversal of 202085721891 is 198127580202.

It is not a de Polignac number, because 202085721891 - 2¹⁰ = 202085720867 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (202085721841) 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, 672906 + ... + 925728.

Almost surely, 2^202085721891 is an apocalyptic number.

202085721891 is a deficient number, since it is larger than the sum of its proper divisors (89820317677).

202085721891 is a wasteful number, since it uses less digits than its factorization.

202085721891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 341642 (or 341639 counting only the distinct ones).

The product of its (nonzero) digits is 161280, while the sum is 45.

The spelling of 202085721891 in words is "two hundred two billion, eighty-five million, seven hundred twenty-one thousand, eight hundred ninety-one".