121644647 has 4 divisors (see below), whose sum is σ = 125839320. Its totient is φ = 117449976.

The previous prime is 121644623. The next prime is 121644659. The reversal of 121644647 is 746446121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121644647 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 (121644617) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2097293 + ... + 2097350.

It is an arithmetic number, because the mean of its divisors is an integer number (31459830).

Almost surely, 2^121644647 is an apocalyptic number.

121644647 is a deficient number, since it is larger than the sum of its proper divisors (4194673).

121644647 is an equidigital number, since it uses as much as digits as its factorization.

121644647 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4194672.

The product of its digits is 32256, while the sum is 35.

The square root of 121644647 is about 11029.2632120192. The cubic root of 121644647 is about 495.4855583059.

The spelling of 121644647 in words is "one hundred twenty-one million, six hundred forty-four thousand, six hundred forty-seven".