869921280 has 240 divisors, whose sum is σ = 3191440824. Its totient is φ = 218234880.

The previous prime is 869921267. The next prime is 869921281. The reversal of 869921280 is 82129968.

It can be written as a sum of positive squares in 4 ways, for example, as 826677504 + 43243776 = 28752^2 + 6576^2 .

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (869921281) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 390570 + ... + 392790.

Almost surely, 2^869921280 is an apocalyptic number.

869921280 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 869921280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1595720412).

869921280 is an abundant number, since it is smaller than the sum of its proper divisors (2321519544).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

869921280 is a wasteful number, since it uses less digits than its factorization.

869921280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2267 (or 2248 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 45.

The square root of 869921280 is about 29494.4279483431. The cubic root of 869921280 is about 954.6114772391.

The spelling of 869921280 in words is "eight hundred sixty-nine million, nine hundred twenty-one thousand, two hundred eighty".