77865481 has 4 divisors (see below), whose sum is σ = 78851200. Its totient is φ = 76879764.

The previous prime is 77865479. The next prime is 77865497. The reversal of 77865481 is 18456877.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 18456877 = 439 ⋅42043.

It is a cyclic number.

It is not a de Polignac number, because 77865481 - 2¹ = 77865479 is a prime.

It is a super-2 number, since 2×77865481² = 12126066262722722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77865881) 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, 492741 + ... + 492898.

It is an arithmetic number, because the mean of its divisors is an integer number (19712800).

Almost surely, 2^77865481 is an apocalyptic number.

It is an amenable number.

77865481 is a deficient number, since it is larger than the sum of its proper divisors (985719).

77865481 is an equidigital number, since it uses as much as digits as its factorization.

77865481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 985718.

The product of its digits is 376320, while the sum is 46.

The square root of 77865481 is about 8824.1419412881. The cubic root of 77865481 is about 427.0201055641.

The spelling of 77865481 in words is "seventy-seven million, eight hundred sixty-five thousand, four hundred eighty-one".