8242156121 has 4 divisors (see below), whose sum is σ = 8726988852. Its totient is φ = 7757323392.

The previous prime is 8242156103. The next prime is 8242156127. The reversal of 8242156121 is 1216512428.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 4615707721 + 3626448400 = 67939^2 + 60220^2 .

It is a cyclic number.

It is not a de Polignac number, because 8242156121 - 2¹⁸ = 8241893977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8242156127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 242416340 + ... + 242416373.

It is an arithmetic number, because the mean of its divisors is an integer number (2181747213).

Almost surely, 2^8242156121 is an apocalyptic number.

It is an amenable number.

8242156121 is a deficient number, since it is larger than the sum of its proper divisors (484832731).

8242156121 is a wasteful number, since it uses less digits than its factorization.

8242156121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 484832730.

The product of its digits is 7680, while the sum is 32.

The square root of 8242156121 is about 90786.3212218669. The cubic root of 8242156121 is about 2019.9794234580.

Adding to 8242156121 its reverse (1216512428), we get a palindrome (9458668549).

The spelling of 8242156121 in words is "eight billion, two hundred forty-two million, one hundred fifty-six thousand, one hundred twenty-one".