121389940 has 72 divisors (see below), whose sum is σ = 302020992. Its totient is φ = 40145280.

The previous prime is 121389937. The next prime is 121389943. The reversal of 121389940 is 49983121.

It is an interprime number because it is at equal distance from previous prime (121389937) and next prime (121389943).

It is a self number, because there is not a number n which added to its sum of digits gives 121389940.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121389943) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 117225 + ... + 118255.

It is an arithmetic number, because the mean of its divisors is an integer number (4194736).

Almost surely, 2^121389940 is an apocalyptic number.

121389940 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121389940, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (151010496).

121389940 is an abundant number, since it is smaller than the sum of its proper divisors (180631052).

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

121389940 is a wasteful number, since it uses less digits than its factorization.

121389940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1105 (or 1074 counting only the distinct ones).

The product of its (nonzero) digits is 15552, while the sum is 37.

The square root of 121389940 is about 11017.7102884402. The cubic root of 121389940 is about 495.1394906679.

The spelling of 121389940 in words is "one hundred twenty-one million, three hundred eighty-nine thousand, nine hundred forty".