121399518 has 16 divisors (see below), whose sum is σ = 243198720. Its totient is φ = 40399896.

The previous prime is 121399501. The next prime is 121399519. The reversal of 121399518 is 815993121.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121399519) 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, 12630 + ... + 20057.

It is an arithmetic number, because the mean of its divisors is an integer number (15199920).

Almost surely, 2^121399518 is an apocalyptic number.

121399518 is an abundant number, since it is smaller than the sum of its proper divisors (121799202).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

121399518 is a wasteful number, since it uses less digits than its factorization.

121399518 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33311.

The product of its digits is 19440, while the sum is 39.

The square root of 121399518 is about 11018.1449436827. The cubic root of 121399518 is about 495.1525129477.

The spelling of 121399518 in words is "one hundred twenty-one million, three hundred ninety-nine thousand, five hundred eighteen".