80011721 has 2 divisors, whose sum is σ = 80011722. Its totient is φ = 80011720.

The previous prime is 80011697. The next prime is 80011769. The reversal of 80011721 is 12711008.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 74304400 + 5707321 = 8620^2 + 2389^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-80011721 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 80011693 and 80011702.

It is not a weakly prime, because it can be changed into another prime (80016721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40005860 + 40005861.

It is an arithmetic number, because the mean of its divisors is an integer number (40005861).

Almost surely, 2^80011721 is an apocalyptic number.

It is an amenable number.

80011721 is a deficient number, since it is larger than the sum of its proper divisors (1).

80011721 is an equidigital number, since it uses as much as digits as its factorization.

80011721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 112, while the sum is 20.

The square root of 80011721 is about 8944.9271098204. The cubic root of 80011721 is about 430.9079804196.

Adding to 80011721 its reverse (12711008), we get a palindrome (92722729).

It can be divided in two parts, 800 and 11721, that added together give a palindrome (12521).

The spelling of 80011721 in words is "eighty million, eleven thousand, seven hundred twenty-one".