77442940381 has 4 divisors (see below), whose sum is σ = 78503802652. Its totient is φ = 76382078112.

The previous prime is 77442940363. The next prime is 77442940429. The reversal of 77442940381 is 18304924477.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 30974240025 + 46468700356 = 175995^2 + 215566^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-77442940381 is a prime.

It is a super-3 number, since 3×77442940381³ (a number of 34 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77442940181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 530431026 + ... + 530431171.

It is an arithmetic number, because the mean of its divisors is an integer number (19625950663).

Almost surely, 2^77442940381 is an apocalyptic number.

It is an amenable number.

77442940381 is a deficient number, since it is larger than the sum of its proper divisors (1060862271).

77442940381 is a wasteful number, since it uses less digits than its factorization.

77442940381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1060862270.

The product of its (nonzero) digits is 1354752, while the sum is 49.

The spelling of 77442940381 in words is "seventy-seven billion, four hundred forty-two million, nine hundred forty thousand, three hundred eighty-one".