87404028121 has 4 divisors (see below), whose sum is σ = 87437531700. Its totient is φ = 87370524544.

The previous prime is 87404028109. The next prime is 87404028161. The reversal of 87404028121 is 12182040478.

It is a happy number.

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 73949188096 + 13454840025 = 271936^2 + 115995^2 .

It is a cyclic number.

It is not a de Polignac number, because 87404028121 - 2²⁷ = 87269810393 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (87404028161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16747876 + ... + 16753093.

It is an arithmetic number, because the mean of its divisors is an integer number (21859382925).

Almost surely, 2^87404028121 is an apocalyptic number.

It is an amenable number.

87404028121 is a deficient number, since it is larger than the sum of its proper divisors (33503579).

87404028121 is a wasteful number, since it uses less digits than its factorization.

87404028121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33503578.

The product of its (nonzero) digits is 28672, while the sum is 37.

Adding to 87404028121 its reverse (12182040478), we get a palindrome (99586068599).

The spelling of 87404028121 in words is "eighty-seven billion, four hundred four million, twenty-eight thousand, one hundred twenty-one".