122718821 has 4 divisors (see below), whose sum is σ = 122740992. Its totient is φ = 122696652.

The previous prime is 122718803. The next prime is 122718829. The reversal of 122718821 is 128817221.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 128817221 = 13 ⋅9909017.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-122718821 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 (122718829) 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, 4946 + ... + 16428.

It is an arithmetic number, because the mean of its divisors is an integer number (30685248).

Almost surely, 2^122718821 is an apocalyptic number.

It is an amenable number.

122718821 is a deficient number, since it is larger than the sum of its proper divisors (22171).

122718821 is a wasteful number, since it uses less digits than its factorization.

122718821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22170.

The product of its digits is 3584, while the sum is 32.

The square root of 122718821 is about 11077.8527251449. The cubic root of 122718821 is about 496.9397357792.

The spelling of 122718821 in words is "one hundred twenty-two million, seven hundred eighteen thousand, eight hundred twenty-one".