121531530 has 16 divisors (see below), whose sum is σ = 291675744. Its totient is φ = 32408400.

The previous prime is 121531523. The next prime is 121531537. The reversal of 121531530 is 35135121.

It is an interprime number because it is at equal distance from previous prime (121531523) and next prime (121531537).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 121531497 and 121531506.

It is not an unprimeable number, because it can be changed into a prime (121531537) 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, 2025496 + ... + 2025555.

It is an arithmetic number, because the mean of its divisors is an integer number (18229734).

Almost surely, 2^121531530 is an apocalyptic number.

121531530 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

121531530 is an abundant number, since it is smaller than the sum of its proper divisors (170144214).

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

121531530 is a wasteful number, since it uses less digits than its factorization.

121531530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4051061.

The product of its (nonzero) digits is 450, while the sum is 21.

The square root of 121531530 is about 11024.1339795922. The cubic root of 121531530 is about 495.3319271538.

Adding to 121531530 its reverse (35135121), we get a palindrome (156666651).

The spelling of 121531530 in words is "one hundred twenty-one million, five hundred thirty-one thousand, five hundred thirty".