8778451321 has 4 divisors (see below), whose sum is σ = 8944082532. Its totient is φ = 8612820112.

The previous prime is 8778451309. The next prime is 8778451327. The reversal of 8778451321 is 1231548778.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1231548778 = 2 ⋅615774389.

It can be written as a sum of positive squares in 2 ways, for example, as 3535967296 + 5242484025 = 59464^2 + 72405^2 .

It is a cyclic number.

It is not a de Polignac number, because 8778451321 - 2⁹ = 8778450809 is a prime.

It is a super-2 number, since 2×8778451321² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8778451327) 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, 82815526 + ... + 82815631.

It is an arithmetic number, because the mean of its divisors is an integer number (2236020633).

Almost surely, 2^8778451321 is an apocalyptic number.

It is an amenable number.

8778451321 is a deficient number, since it is larger than the sum of its proper divisors (165631211).

8778451321 is a wasteful number, since it uses less digits than its factorization.

8778451321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165631210.

The product of its digits is 376320, while the sum is 46.

The square root of 8778451321 is about 93693.3899536141. The cubic root of 8778451321 is about 2062.8736813518.

The spelling of 8778451321 in words is "eight billion, seven hundred seventy-eight million, four hundred fifty-one thousand, three hundred twenty-one".