191320020121 has 4 divisors (see below), whose sum is σ = 192465649152. Its totient is φ = 190174391092.

The previous prime is 191320020119. The next prime is 191320020149. The reversal of 191320020121 is 121020023191.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 191320020121 - 2¹ = 191320020119 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 191320020092 and 191320020101.

It is not an unprimeable number, because it can be changed into a prime (191320027121) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 572814265 + ... + 572814598.

It is an arithmetic number, because the mean of its divisors is an integer number (48116412288).

Almost surely, 2^191320020121 is an apocalyptic number.

It is an amenable number.

191320020121 is a deficient number, since it is larger than the sum of its proper divisors (1145629031).

191320020121 is a wasteful number, since it uses less digits than its factorization.

191320020121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1145629030.

The product of its (nonzero) digits is 216, while the sum is 22.

The spelling of 191320020121 in words is "one hundred ninety-one billion, three hundred twenty million, twenty thousand, one hundred twenty-one".