121685091 has 8 divisors (see below), whose sum is σ = 176996544. Its totient is φ = 73748520.

The previous prime is 121685077. The next prime is 121685107. The reversal of 121685091 is 190586121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 121685091 - 2¹⁰ = 121684067 is a prime.

It is a super-2 number, since 2×121685091² = 29614522743356562, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (33), and also a Moran number because the ratio is a prime number: 3687427 = 121685091 / (1 + 2 + 1 + 6 + 8 + 5 + 0 + 9 + 1).

It is not an unprimeable number, because it can be changed into a prime (121685041) 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 7 ways as a sum of consecutive naturals, for example, 1843681 + ... + 1843746.

It is an arithmetic number, because the mean of its divisors is an integer number (22124568).

Almost surely, 2^121685091 is an apocalyptic number.

121685091 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

121685091 is a deficient number, since it is larger than the sum of its proper divisors (55311453).

121685091 is a wasteful number, since it uses less digits than its factorization.

121685091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3687441.

The product of its (nonzero) digits is 4320, while the sum is 33.

The square root of 121685091 is about 11031.0965456749. The cubic root of 121685091 is about 495.5404646744.

The spelling of 121685091 in words is "one hundred twenty-one million, six hundred eighty-five thousand, ninety-one".