77641481 has 2 divisors, whose sum is σ = 77641482. Its totient is φ = 77641480.

The previous prime is 77641477. The next prime is 77641483. The reversal of 77641481 is 18414677.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 59151481 + 18490000 = 7691^2 + 4300^2 .

It is an emirp because it is prime and its reverse (18414677) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 77641481 - 2² = 77641477 is a prime.

It is a super-2 number, since 2×77641481² = 12056399143746722, which contains 22 as substring.

Together with 77641483, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (77641483) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38820740 + 38820741.

It is an arithmetic number, because the mean of its divisors is an integer number (38820741).

Almost surely, 2^77641481 is an apocalyptic number.

It is an amenable number.

77641481 is a deficient number, since it is larger than the sum of its proper divisors (1).

77641481 is an equidigital number, since it uses as much as digits as its factorization.

77641481 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 37632, while the sum is 38.

The square root of 77641481 is about 8811.4403476390. The cubic root of 77641481 is about 426.6102347104.

The spelling of 77641481 in words is "seventy-seven million, six hundred forty-one thousand, four hundred eighty-one".