77781241 has 4 divisors (see below), whose sum is σ = 77805684. Its totient is φ = 77756800.

The previous prime is 77781233. The next prime is 77781247. The reversal of 77781241 is 14218777.

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 19105641 + 58675600 = 4371^2 + 7660^2 .

It is a cyclic number.

It is not a de Polignac number, because 77781241 - 2³ = 77781233 is a prime.

It is a deceptive number, since it divides R_77781240.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 77781241.

It is not an unprimeable number, because it can be changed into a prime (77781247) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6580 + ... + 14101.

It is an arithmetic number, because the mean of its divisors is an integer number (19451421).

Almost surely, 2^77781241 is an apocalyptic number.

It is an amenable number.

77781241 is a deficient number, since it is larger than the sum of its proper divisors (24443).

77781241 is a wasteful number, since it uses less digits than its factorization.

77781241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24442.

The product of its digits is 21952, while the sum is 37.

The square root of 77781241 is about 8819.3673809407. The cubic root of 77781241 is about 426.8660571831.

The spelling of 77781241 in words is "seventy-seven million, seven hundred eighty-one thousand, two hundred forty-one".