80646749 has 2 divisors, whose sum is σ = 80646750. Its totient is φ = 80646748.

The previous prime is 80646743. The next prime is 80646757. The reversal of 80646749 is 94764608.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 73650724 + 6996025 = 8582^2 + 2645^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-80646749 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (80646743) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40323374 + 40323375.

It is an arithmetic number, because the mean of its divisors is an integer number (40323375).

Almost surely, 2^80646749 is an apocalyptic number.

It is an amenable number.

80646749 is a deficient number, since it is larger than the sum of its proper divisors (1).

80646749 is an equidigital number, since it uses as much as digits as its factorization.

80646749 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 290304, while the sum is 44.

The square root of 80646749 is about 8980.3535008373. The cubic root of 80646749 is about 432.0449716700.

The spelling of 80646749 in words is "eighty million, six hundred forty-six thousand, seven hundred forty-nine".