121698890 has 16 divisors (see below), whose sum is σ = 219426408. Its totient is φ = 48597696.

The previous prime is 121698851. The next prime is 121698919. The reversal of 121698890 is 98896121.

It can be written as a sum of positive squares in 4 ways, for example, as 34070569 + 87628321 = 5837^2 + 9361^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3797 + ... + 16056.

Almost surely, 2^121698890 is an apocalyptic number.

121698890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

121698890 is a deficient number, since it is larger than the sum of its proper divisors (97727518).

121698890 is a wasteful number, since it uses less digits than its factorization.

121698890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20473.

The product of its (nonzero) digits is 62208, while the sum is 44.

The square root of 121698890 is about 11031.7219870698. The cubic root of 121698890 is about 495.5591952748.

The spelling of 121698890 in words is "one hundred twenty-one million, six hundred ninety-eight thousand, eight hundred ninety".