243121540225 has 12 divisors (see below), whose sum is σ = 302310472320. Its totient is φ = 193955450000.

The previous prime is 243121540213. The next prime is 243121540237. The reversal of 243121540225 is 522045121342.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (243121540213) and next prime (243121540237).

It is not a de Polignac number, because 243121540225 - 2³⁷ = 105682586753 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13535401 + ... + 13553350.

It is an arithmetic number, because the mean of its divisors is an integer number (25192539360).

Almost surely, 2^243121540225 is an apocalyptic number.

243121540225 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

243121540225 is a deficient number, since it is larger than the sum of its proper divisors (59188932095).

243121540225 is a wasteful number, since it uses less digits than its factorization.

243121540225 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27089120 (or 27089115 counting only the distinct ones).

The product of its (nonzero) digits is 19200, while the sum is 31.

Adding to 243121540225 its reverse (522045121342), we get a palindrome (765166661567).

The spelling of 243121540225 in words is "two hundred forty-three billion, one hundred twenty-one million, five hundred forty thousand, two hundred twenty-five".