121215513 has 4 divisors (see below), whose sum is σ = 161620688. Its totient is φ = 80810340.

The previous prime is 121215511. The next prime is 121215527. The reversal of 121215513 is 315512121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 121215513 - 2¹ = 121215511 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 121215513.

It is not an unprimeable number, because it can be changed into a prime (121215511) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20202583 + ... + 20202588.

It is an arithmetic number, because the mean of its divisors is an integer number (40405172).

Almost surely, 2^121215513 is an apocalyptic number.

It is an amenable number.

121215513 is a deficient number, since it is larger than the sum of its proper divisors (40405175).

121215513 is an equidigital number, since it uses as much as digits as its factorization.

121215513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40405174.

The product of its digits is 300, while the sum is 21.

The square root of 121215513 is about 11009.7916874026. The cubic root of 121215513 is about 494.9022192330.

Adding to 121215513 its reverse (315512121), we get a palindrome (436727634).

The spelling of 121215513 in words is "one hundred twenty-one million, two hundred fifteen thousand, five hundred thirteen".