88396821521 has 4 divisors (see below), whose sum is σ = 90064686132. Its totient is φ = 86728956912.

The previous prime is 88396821503. The next prime is 88396821571. The reversal of 88396821521 is 12512869388.

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 60920112400 + 27476709121 = 246820^2 + 165761^2 .

It is a cyclic number.

It is not a de Polignac number, because 88396821521 - 2¹⁴ = 88396805137 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (53), and also a Moran number because the ratio is a prime number: 1667864557 = 88396821521 / (8 + 8 + 3 + 9 + 6 + 8 + 2 + 1 + 5 + 2 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (88396821571) 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, 833932226 + ... + 833932331.

It is an arithmetic number, because the mean of its divisors is an integer number (22516171533).

Almost surely, 2^88396821521 is an apocalyptic number.

It is an amenable number.

88396821521 is a deficient number, since it is larger than the sum of its proper divisors (1667864611).

88396821521 is a wasteful number, since it uses less digits than its factorization.

88396821521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1667864610.

The product of its digits is 1658880, while the sum is 53.

The spelling of 88396821521 in words is "eighty-eight billion, three hundred ninety-six million, eight hundred twenty-one thousand, five hundred twenty-one".