77838817 has 4 divisors (see below), whose sum is σ = 88958656. Its totient is φ = 66718980.

The previous prime is 77838797. The next prime is 77838823. The reversal of 77838817 is 71883877.

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: 71883877 = 13 ⋅5529529.

It is a cyclic number.

It is not a de Polignac number, because 77838817 - 2⁷ = 77838689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77838847) 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, 5559909 + ... + 5559922.

It is an arithmetic number, because the mean of its divisors is an integer number (22239664).

Almost surely, 2^77838817 is an apocalyptic number.

It is an amenable number.

77838817 is a deficient number, since it is larger than the sum of its proper divisors (11119839).

77838817 is a wasteful number, since it uses less digits than its factorization.

77838817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11119838.

The product of its digits is 526848, while the sum is 49.

The square root of 77838817 is about 8822.6309568065. The cubic root of 77838817 is about 426.9713575443.

The spelling of 77838817 in words is "seventy-seven million, eight hundred thirty-eight thousand, eight hundred seventeen".