80878721 has 24 divisors (see below), whose sum is σ = 104288832. Its totient is φ = 60933600.

The previous prime is 80878643. The next prime is 80878723. The reversal of 80878721 is 12787808.

It is not a de Polignac number, because 80878721 - 2¹⁴ = 80862337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (80878723) 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, 73451 + ... + 74543.

It is an arithmetic number, because the mean of its divisors is an integer number (4345368).

Almost surely, 2^80878721 is an apocalyptic number.

It is an amenable number.

80878721 is a deficient number, since it is larger than the sum of its proper divisors (23410111).

80878721 is a wasteful number, since it uses less digits than its factorization.

80878721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1173 (or 1142 counting only the distinct ones).

The product of its (nonzero) digits is 50176, while the sum is 41.

The square root of 80878721 is about 8993.2597538379. The cubic root of 80878721 is about 432.4588192940.

It can be divided in two parts, 808787 and 21, that added together give a palindrome (808808).

The spelling of 80878721 in words is "eighty million, eight hundred seventy-eight thousand, seven hundred twenty-one".