121099990 has 16 divisors (see below), whose sum is σ = 237796560. Its totient is φ = 44036320.

The previous prime is 121099987. The next prime is 121099999. The reversal of 121099990 is 99990121.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121099999) 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, 550345 + ... + 550564.

It is an arithmetic number, because the mean of its divisors is an integer number (14862285).

Almost surely, 2^121099990 is an apocalyptic number.

121099990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

121099990 is a deficient number, since it is larger than the sum of its proper divisors (116696570).

121099990 is a wasteful number, since it uses less digits than its factorization.

121099990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1100927.

The product of its (nonzero) digits is 13122, while the sum is 40.

The square root of 121099990 is about 11004.5440614321. The cubic root of 121099990 is about 494.7449490404.

The spelling of 121099990 in words is "one hundred twenty-one million, ninety-nine thousand, nine hundred ninety".