121953912661 has 8 divisors (see below), whose sum is σ = 139378719680. Its totient is φ = 104529810528.

The previous prime is 121953912649. The next prime is 121953912679. The reversal of 121953912661 is 166219359121.

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 121953912661 - 2⁷ = 121953912533 is a prime.

It is a super-2 number, since 2×121953912661² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121953912631) 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, 269785 + ... + 562753.

It is an arithmetic number, because the mean of its divisors is an integer number (17422339960).

Almost surely, 2^121953912661 is an apocalyptic number.

It is an amenable number.

121953912661 is a deficient number, since it is larger than the sum of its proper divisors (17424807019).

121953912661 is an equidigital number, since it uses as much as digits as its factorization.

121953912661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 352443.

The product of its digits is 174960, while the sum is 46.

The spelling of 121953912661 in words is "one hundred twenty-one billion, nine hundred fifty-three million, nine hundred twelve thousand, six hundred sixty-one".