121694631721 has 8 divisors (see below), whose sum is σ = 131176338944. Its totient is φ = 112230150480.

The previous prime is 121694631683. The next prime is 121694631727. The reversal of 121694631721 is 127136496121.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 121694631721 - 2¹⁹ = 121694107433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121694631727) 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, 4291815 + ... + 4320076.

It is an arithmetic number, because the mean of its divisors is an integer number (16397042368).

Almost surely, 2^121694631721 is an apocalyptic number.

It is an amenable number.

121694631721 is a deficient number, since it is larger than the sum of its proper divisors (9481707223).

121694631721 is a wasteful number, since it uses less digits than its factorization.

121694631721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8612991.

The product of its digits is 108864, while the sum is 43.

The spelling of 121694631721 in words is "one hundred twenty-one billion, six hundred ninety-four million, six hundred thirty-one thousand, seven hundred twenty-one".