80781641 has 2 divisors, whose sum is σ = 80781642. Its totient is φ = 80781640.

The previous prime is 80781607. The next prime is 80781643. The reversal of 80781641 is 14618708.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 73599241 + 7182400 = 8579^2 + 2680^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-80781641 is a prime.

Together with 80781643, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (80781643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40390820 + 40390821.

It is an arithmetic number, because the mean of its divisors is an integer number (40390821).

Almost surely, 2^80781641 is an apocalyptic number.

It is an amenable number.

80781641 is a deficient number, since it is larger than the sum of its proper divisors (1).

80781641 is an equidigital number, since it uses as much as digits as its factorization.

80781641 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10752, while the sum is 35.

The square root of 80781641 is about 8987.8607577109. The cubic root of 80781641 is about 432.2857209787.

The spelling of 80781641 in words is "eighty million, seven hundred eighty-one thousand, six hundred forty-one".