77378819 has 4 divisors (see below), whose sum is σ = 88432944. Its totient is φ = 66324696.

The previous prime is 77378813. The next prime is 77378839. The reversal of 77378819 is 91887377.

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 77378819 - 2¹⁶ = 77313283 is a prime.

It is a super-2 number, since 2×77378819² = 11974963259669522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (77378813) 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, 5527052 + ... + 5527065.

It is an arithmetic number, because the mean of its divisors is an integer number (22108236).

Almost surely, 2^77378819 is an apocalyptic number.

77378819 is a deficient number, since it is larger than the sum of its proper divisors (11054125).

77378819 is a wasteful number, since it uses less digits than its factorization.

77378819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11054124.

The product of its digits is 592704, while the sum is 50.

The square root of 77378819 is about 8796.5231199605. The cubic root of 77378819 is about 426.1286154593.

The spelling of 77378819 in words is "seventy-seven million, three hundred seventy-eight thousand, eight hundred nineteen".