77686945 has 16 divisors (see below), whose sum is σ = 106829568. Its totient is φ = 53127360.

The previous prime is 77686937. The next prime is 77686949. The reversal of 77686945 is 54968677.

It is a happy number.

It is not a de Polignac number, because 77686945 - 2³ = 77686937 is a prime.

It is a super-2 number, since 2×77686945² = 12070522846866050, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 77686892 and 77686901.

It is not an unprimeable number, because it can be changed into a prime (77686949) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11100 + ... + 16690.

It is an arithmetic number, because the mean of its divisors is an integer number (6676848).

Almost surely, 2^77686945 is an apocalyptic number.

It is an amenable number.

77686945 is a deficient number, since it is larger than the sum of its proper divisors (29142623).

77686945 is a wasteful number, since it uses less digits than its factorization.

77686945 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6000.

The product of its digits is 2540160, while the sum is 52.

The square root of 77686945 is about 8814.0197980263. The cubic root of 77686945 is about 426.6934875582.

The spelling of 77686945 in words is "seventy-seven million, six hundred eighty-six thousand, nine hundred forty-five".