121523540 has 48 divisors (see below), whose sum is σ = 264955152. Its totient is φ = 46780416.

The previous prime is 121523491. The next prime is 121523569. The reversal of 121523540 is 45325121.

It can be written as a sum of positive squares in 8 ways, for example, as 611524 + 120912016 = 782^2 + 10996^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 70934 + ... + 72626.

It is an arithmetic number, because the mean of its divisors is an integer number (5519899).

Almost surely, 2^121523540 is an apocalyptic number.

121523540 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 121523540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (132477576).

121523540 is an abundant number, since it is smaller than the sum of its proper divisors (143431612).

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

121523540 is a wasteful number, since it uses less digits than its factorization.

121523540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1836 (or 1834 counting only the distinct ones).

The product of its (nonzero) digits is 1200, while the sum is 23.

The square root of 121523540 is about 11023.7715868935. The cubic root of 121523540 is about 495.3210718396.

Adding to 121523540 its reverse (45325121), we get a palindrome (166848661).

The spelling of 121523540 in words is "one hundred twenty-one million, five hundred twenty-three thousand, five hundred forty".