121540540 has 48 divisors (see below), whose sum is σ = 280959840. Its totient is φ = 43796480.

The previous prime is 121540513. The next prime is 121540541. The reversal of 121540540 is 45045121.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121540541) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22416 + ... + 27304.

It is an arithmetic number, because the mean of its divisors is an integer number (5853330).

Almost surely, 2^121540540 is an apocalyptic number.

121540540 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 121540540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (140479920).

121540540 is an abundant number, since it is smaller than the sum of its proper divisors (159419300).

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

121540540 is a wasteful number, since it uses less digits than its factorization.

121540540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5022 (or 5020 counting only the distinct ones).

The product of its (nonzero) digits is 800, while the sum is 22.

The square root of 121540540 is about 11024.5426208982. The cubic root of 121540540 is about 495.3441676821.

Adding to 121540540 its reverse (45045121), we get a palindrome (166585661).

The spelling of 121540540 in words is "one hundred twenty-one million, five hundred forty thousand, five hundred forty".