77649691 has 4 divisors (see below), whose sum is σ = 88742512. Its totient is φ = 66556872.

The previous prime is 77649683. The next prime is 77649703. The reversal of 77649691 is 19694677.

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

It is a cyclic number.

It is not a de Polignac number, because 77649691 - 2³ = 77649683 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77649631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5546400 + ... + 5546413.

It is an arithmetic number, because the mean of its divisors is an integer number (22185628).

Almost surely, 2^77649691 is an apocalyptic number.

77649691 is a deficient number, since it is larger than the sum of its proper divisors (11092821).

77649691 is a wasteful number, since it uses less digits than its factorization.

77649691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11092820.

The product of its digits is 571536, while the sum is 49.

The square root of 77649691 is about 8811.9062069452. The cubic root of 77649691 is about 426.6252711168.

The spelling of 77649691 in words is "seventy-seven million, six hundred forty-nine thousand, six hundred ninety-one".