121620789 has 6 divisors (see below), whose sum is σ = 175674486. Its totient is φ = 81080520.

The previous prime is 121620787. The next prime is 121620797. The reversal of 121620789 is 987026121.

121620789 is a `hidden beast` number, since 1 + 21 + 620 + 7 + 8 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 121220100 + 400689 = 11010^2 + 633^2 .

It is not a de Polignac number, because 121620789 - 2¹ = 121620787 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121620787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6756702 + ... + 6756719.

It is an arithmetic number, because the mean of its divisors is an integer number (29279081).

Almost surely, 2^121620789 is an apocalyptic number.

It is an amenable number.

121620789 is a deficient number, since it is larger than the sum of its proper divisors (54053697).

121620789 is a wasteful number, since it uses less digits than its factorization.

121620789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13513427 (or 13513424 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 36.

The square root of 121620789 is about 11028.1815817477. The cubic root of 121620789 is about 495.4531632173.

The spelling of 121620789 in words is "one hundred twenty-one million, six hundred twenty thousand, seven hundred eighty-nine".