669141996121 has 3 divisors (see below), whose sum is σ = 669142814133. Its totient is φ = 669141178110.

The previous prime is 669141996101. The next prime is 669141996209. The reversal of 669141996121 is 121699141966.

The square root of 669141996121 is 818011.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 669141996121 - 2¹³ = 669141987929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (669141996101) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 409006 + ... + 1227016.

It is an arithmetic number, because the mean of its divisors is an integer number (223047604711).

Almost surely, 2^669141996121 is an apocalyptic number.

669141996121 is the 818011-st square number.

669141996121 is the 409006-th centered octagonal number.

It is an amenable number.

669141996121 is a deficient number, since it is larger than the sum of its proper divisors (818012).

669141996121 is an frugal number, since it uses more digits than its factorization.

669141996121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1636022 (or 818011 counting only the distinct ones).

The product of its digits is 1259712, while the sum is 55.

The spelling of 669141996121 in words is "six hundred sixty-nine billion, one hundred forty-one million, nine hundred ninety-six thousand, one hundred twenty-one".