68921280 has 140 divisors (see below), whose sum is σ = 245257320. Its totient is φ = 18372096.

The previous prime is 68921239. The next prime is 68921309. The reversal of 68921280 is 8212986.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 24591 + ... + 27249.

It is an arithmetic number, because the mean of its divisors is an integer number (1751838).

Almost surely, 2^68921280 is an apocalyptic number.

68921280 is a gapful number since it is divisible by the number (60) 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 68921280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (122628660).

68921280 is an abundant number, since it is smaller than the sum of its proper divisors (176336040).

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

68921280 is a wasteful number, since it uses less digits than its factorization.

68921280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2688 (or 2669 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 68921280 is about 8301.8841234987. The cubic root of 68921280 is about 410.0005552243. Note that the first 3 decimals are identical.

The spelling of 68921280 in words is "sixty-eight million, nine hundred twenty-one thousand, two hundred eighty".