121990111 has 8 divisors (see below), whose sum is σ = 124761600. Its totient is φ = 119242200.

The previous prime is 121990109. The next prime is 121990133. The reversal of 121990111 is 111099121.

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

It is a cyclic number.

It is not a de Polignac number, because 121990111 - 2¹ = 121990109 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121990151) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4786 + ... + 16336.

It is an arithmetic number, because the mean of its divisors is an integer number (15595200).

Almost surely, 2^121990111 is an apocalyptic number.

121990111 is a deficient number, since it is larger than the sum of its proper divisors (2771489).

121990111 is a wasteful number, since it uses less digits than its factorization.

121990111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11789.

The product of its (nonzero) digits is 162, while the sum is 25.

The square root of 121990111 is about 11044.9133541192. The cubic root of 121990111 is about 495.9541654121.

The spelling of 121990111 in words is "one hundred twenty-one million, nine hundred ninety thousand, one hundred eleven".