77820007 has 2 divisors, whose sum is σ = 77820008. Its totient is φ = 77820006.

The previous prime is 77819941. The next prime is 77820019. The reversal of 77820007 is 70002877.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77820007 is a prime.

It is equal to p_4549621 and since 77820007 and 4549621 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 (77820037) 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, 38910003 + 38910004.

It is an arithmetic number, because the mean of its divisors is an integer number (38910004).

Almost surely, 2^77820007 is an apocalyptic number.

77820007 is a deficient number, since it is larger than the sum of its proper divisors (1).

77820007 is an equidigital number, since it uses as much as digits as its factorization.

77820007 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5488, while the sum is 31.

The square root of 77820007 is about 8821.5648838514. The cubic root of 77820007 is about 426.9369617738.

The spelling of 77820007 in words is "seventy-seven million, eight hundred twenty thousand, seven".