80206991 has 2 divisors, whose sum is σ = 80206992. Its totient is φ = 80206990.

The previous prime is 80206981. The next prime is 80207063. The reversal of 80206991 is 19960208.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 80206991 - 2¹⁸ = 79944847 is a prime.

It is a super-2 number, since 2×80206991² = 12866322810548162, which contains 22 as substring.

It is a Chen prime.

It is equal to p_4680719 and since 80206991 and 4680719 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (80206981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40103495 + 40103496.

It is an arithmetic number, because the mean of its divisors is an integer number (40103496).

Almost surely, 2^80206991 is an apocalyptic number.

80206991 is a deficient number, since it is larger than the sum of its proper divisors (1).

80206991 is an equidigital number, since it uses as much as digits as its factorization.

80206991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 35.

The square root of 80206991 is about 8955.8355835734. The cubic root of 80206991 is about 431.2582417805.

The spelling of 80206991 in words is "eighty million, two hundred six thousand, nine hundred ninety-one".