195712121 has 4 divisors (see below), whose sum is σ = 213504144. Its totient is φ = 177920100.

The previous prime is 195712079. The next prime is 195712123. The reversal of 195712121 is 121217591.

It is a happy number.

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 195712121 - 2²⁶ = 128603257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (195712123) 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, 8895995 + ... + 8896016.

It is an arithmetic number, because the mean of its divisors is an integer number (53376036).

Almost surely, 2^195712121 is an apocalyptic number.

195712121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

195712121 is a deficient number, since it is larger than the sum of its proper divisors (17792023).

195712121 is a wasteful number, since it uses less digits than its factorization.

195712121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17792022.

The product of its digits is 1260, while the sum is 29.

The square root of 195712121 is about 13989.7148291164. The cubic root of 195712121 is about 580.5940415872.

The spelling of 195712121 in words is "one hundred ninety-five million, seven hundred twelve thousand, one hundred twenty-one".