121651643 has 8 divisors (see below), whose sum is σ = 128912112. Its totient is φ = 114402816.

The previous prime is 121651591. The next prime is 121651667. The reversal of 121651643 is 346156121.

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 121651643 - 2²² = 117457339 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121657643) 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, 28196 + ... + 32222.

It is an arithmetic number, because the mean of its divisors is an integer number (16114014).

Almost surely, 2^121651643 is an apocalyptic number.

121651643 is a deficient number, since it is larger than the sum of its proper divisors (7260469).

121651643 is a wasteful number, since it uses less digits than its factorization.

121651643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5821.

The product of its digits is 4320, while the sum is 29.

The square root of 121651643 is about 11029.5803637310. The cubic root of 121651643 is about 495.4950568757.

The spelling of 121651643 in words is "one hundred twenty-one million, six hundred fifty-one thousand, six hundred forty-three".