80511961 has 2 divisors, whose sum is σ = 80511962. Its totient is φ = 80511960.

The previous prime is 80511943. The next prime is 80511967. The reversal of 80511961 is 16911508.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 67551961 + 12960000 = 8219^2 + 3600^2 .

It is a cyclic number.

It is not a de Polignac number, because 80511961 - 2⁹ = 80511449 is a prime.

It is not a weakly prime, because it can be changed into another prime (80511967) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40255980 + 40255981.

It is an arithmetic number, because the mean of its divisors is an integer number (40255981).

Almost surely, 2^80511961 is an apocalyptic number.

It is an amenable number.

80511961 is a deficient number, since it is larger than the sum of its proper divisors (1).

80511961 is an equidigital number, since it uses as much as digits as its factorization.

80511961 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2160, while the sum is 31.

The square root of 80511961 is about 8972.8457581751. The cubic root of 80511961 is about 431.8041396807.

The spelling of 80511961 in words is "eighty million, five hundred eleven thousand, nine hundred sixty-one".