243121223115 has 16 divisors (see below), whose sum is σ = 432215508000. Its totient is φ = 129664652256.

The previous prime is 243121223087. The next prime is 243121223143. The reversal of 243121223115 is 511322121342.

It is a happy number.

243121223115 is a `hidden beast` number, since 2 + 431 + 2 + 1 + 223 + 1 + 1 + 5 = 666.

It is an interprime number because it is at equal distance from previous prime (243121223087) and next prime (243121223143).

It is not a de Polignac number, because 243121223115 - 2⁵ = 243121223083 is a prime.

It is a super-2 number, since 2×243121223115² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

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, 900448840 + ... + 900449109.

It is an arithmetic number, because the mean of its divisors is an integer number (27013469250).

Almost surely, 2^243121223115 is an apocalyptic number.

243121223115 is a deficient number, since it is larger than the sum of its proper divisors (189094284885).

243121223115 is a wasteful number, since it uses less digits than its factorization.

243121223115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1800897963 (or 1800897957 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

Adding to 243121223115 its reverse (511322121342), we get a palindrome (754443344457).

The spelling of 243121223115 in words is "two hundred forty-three billion, one hundred twenty-one million, two hundred twenty-three thousand, one hundred fifteen".