671205712121 has 4 divisors (see below), whose sum is σ = 767092242432. Its totient is φ = 575319181812.

The previous prime is 671205712087. The next prime is 671205712129. The reversal of 671205712121 is 121217502176.

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 671205712121 - 2⁶ = 671205712057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (671205712129) 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, 47943265145 + ... + 47943265158.

It is an arithmetic number, because the mean of its divisors is an integer number (191773060608).

Almost surely, 2^671205712121 is an apocalyptic number.

It is an amenable number.

671205712121 is a deficient number, since it is larger than the sum of its proper divisors (95886530311).

671205712121 is an equidigital number, since it uses as much as digits as its factorization.

671205712121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95886530310.

The product of its (nonzero) digits is 11760, while the sum is 35.

The spelling of 671205712121 in words is "six hundred seventy-one billion, two hundred five million, seven hundred twelve thousand, one hundred twenty-one".