121644819 has 12 divisors (see below), whose sum is σ = 175855992. Its totient is φ = 81028800.

The previous prime is 121644793. The next prime is 121644823. The reversal of 121644819 is 918446121.

121644819 is a `hidden beast` number, since 1 + 2 + 1 + 644 + 8 + 1 + 9 = 666.

It is not a de Polignac number, because 121644819 - 2⁸ = 121644563 is a prime.

It is a super-2 number, since 2×121644819² = 29594923979085522, which contains 22 as substring.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (121644829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7284 + ... + 17214.

It is an arithmetic number, because the mean of its divisors is an integer number (14654666).

Almost surely, 2^121644819 is an apocalyptic number.

121644819 is a deficient number, since it is larger than the sum of its proper divisors (54211173).

121644819 is a wasteful number, since it uses less digits than its factorization.

121644819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11298 (or 11295 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 121644819 is about 11029.2710094548. The cubic root of 121644819 is about 495.4857918372.

The spelling of 121644819 in words is "one hundred twenty-one million, six hundred forty-four thousand, eight hundred nineteen".