77820738 has 8 divisors (see below), whose sum is σ = 155641488. Its totient is φ = 25940244.

The previous prime is 77820737. The next prime is 77820739. The reversal of 77820738 is 83702877.

It is an interprime number because it is at equal distance from previous prime (77820737) and next prime (77820739).

It is a sphenic number, since it is the product of 3 distinct primes.

77820738 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 77820738.

It is not an unprimeable number, because it can be changed into a prime (77820733) 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, 6485056 + ... + 6485067.

It is an arithmetic number, because the mean of its divisors is an integer number (19455186).

Almost surely, 2^77820738 is an apocalyptic number.

77820738 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

77820738 is a wasteful number, since it uses less digits than its factorization.

77820738 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12970128.

The product of its (nonzero) digits is 131712, while the sum is 42.

The square root of 77820738 is about 8821.6063163122. The cubic root of 77820738 is about 426.9382985764.

The spelling of 77820738 in words is "seventy-seven million, eight hundred twenty thousand, seven hundred thirty-eight".