121999115 has 12 divisors (see below), whose sum is σ = 167402736. Its totient is φ = 83611728.

The previous prime is 121999103. The next prime is 121999117. The reversal of 121999115 is 511999121.

It is not a de Polignac number, because 121999115 - 2¹² = 121995019 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121999117) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 64412 + ... + 66278.

It is an arithmetic number, because the mean of its divisors is an integer number (13950228).

Almost surely, 2^121999115 is an apocalyptic number.

121999115 is a deficient number, since it is larger than the sum of its proper divisors (45403621).

121999115 is an frugal number, since it uses more digits than its factorization.

121999115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3746 (or 1879 counting only the distinct ones).

The product of its digits is 7290, while the sum is 38.

The square root of 121999115 is about 11045.3209550470. The cubic root of 121999115 is about 495.9663671155.

The spelling of 121999115 in words is "one hundred twenty-one million, nine hundred ninety-nine thousand, one hundred fifteen".