202115891 has 4 divisors (see below), whose sum is σ = 204674400. Its totient is φ = 199557384.

The previous prime is 202115833. The next prime is 202115897. The reversal of 202115891 is 198511202.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-202115891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (202115897) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1279136 + ... + 1279293.

It is an arithmetic number, because the mean of its divisors is an integer number (51168600).

Almost surely, 2^202115891 is an apocalyptic number.

202115891 is a deficient number, since it is larger than the sum of its proper divisors (2558509).

202115891 is an equidigital number, since it uses as much as digits as its factorization.

202115891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2558508.

The product of its (nonzero) digits is 1440, while the sum is 29.

The square root of 202115891 is about 14216.7468501060. The cubic root of 202115891 is about 586.8586183538.

The spelling of 202115891 in words is "two hundred two million, one hundred fifteen thousand, eight hundred ninety-one".