77620447 has 2 divisors, whose sum is σ = 77620448. Its totient is φ = 77620446.

The previous prime is 77620427. The next prime is 77620457. The reversal of 77620447 is 74402677.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77620447 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77620427) 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, 38810223 + 38810224.

It is an arithmetic number, because the mean of its divisors is an integer number (38810224).

Almost surely, 2^77620447 is an apocalyptic number.

77620447 is a deficient number, since it is larger than the sum of its proper divisors (1).

77620447 is an equidigital number, since it uses as much as digits as its factorization.

77620447 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 65856, while the sum is 37.

The square root of 77620447 is about 8810.2467048318. The cubic root of 77620447 is about 426.5717066367.

The spelling of 77620447 in words is "seventy-seven million, six hundred twenty thousand, four hundred forty-seven".