121809449782 has 16 divisors (see below), whose sum is σ = 190665692640. Its totient is φ = 58254425152.

The previous prime is 121809449771. The next prime is 121809449789. The reversal of 121809449782 is 287944908121.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121809449789) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2202444 + ... + 2257072.

It is an arithmetic number, because the mean of its divisors is an integer number (11916605790).

Almost surely, 2^121809449782 is an apocalyptic number.

121809449782 is a deficient number, since it is larger than the sum of its proper divisors (68856242858).

121809449782 is a wasteful number, since it uses less digits than its factorization.

121809449782 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 103127.

The product of its (nonzero) digits is 2322432, while the sum is 55.

It can be divided in two parts, 1218094 and 49782, that added together give a square (1267876 = 1126²).

The spelling of 121809449782 in words is "one hundred twenty-one billion, eight hundred nine million, four hundred forty-nine thousand, seven hundred eighty-two".