87842354821 has 4 divisors (see below), whose sum is σ = 94599459052. Its totient is φ = 81085250592.

The previous prime is 87842354779. The next prime is 87842354861. The reversal of 87842354821 is 12845324878.

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 57653292321 + 30189062500 = 240111^2 + 173750^2 .

It is a cyclic number.

It is not a de Polignac number, because 87842354821 - 2⁷ = 87842354693 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (87842354861) 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, 3378552096 + ... + 3378552121.

It is an arithmetic number, because the mean of its divisors is an integer number (23649864763).

Almost surely, 2^87842354821 is an apocalyptic number.

It is an amenable number.

87842354821 is a deficient number, since it is larger than the sum of its proper divisors (6757104231).

87842354821 is a wasteful number, since it uses less digits than its factorization.

87842354821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6757104230.

The product of its digits is 3440640, while the sum is 52.

The spelling of 87842354821 in words is "eighty-seven billion, eight hundred forty-two million, three hundred fifty-four thousand, eight hundred twenty-one".