121661661671 has 8 divisors (see below), whose sum is σ = 135545681664. Its totient is φ = 108248286520.

The previous prime is 121661661601. The next prime is 121661661673. The reversal of 121661661671 is 176166166121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 121661661671 - 2¹⁸ = 121661399527 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121661661673) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 117660665 + ... + 117661698.

It is an arithmetic number, because the mean of its divisors is an integer number (16943210208).

Almost surely, 2^121661661671 is an apocalyptic number.

121661661671 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

121661661671 is a deficient number, since it is larger than the sum of its proper divisors (13884019993).

121661661671 is a wasteful number, since it uses less digits than its factorization.

121661661671 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 235322421.

The product of its digits is 108864, while the sum is 44.

The spelling of 121661661671 in words is "one hundred twenty-one billion, six hundred sixty-one million, six hundred sixty-one thousand, six hundred seventy-one".