78587645377 has 4 divisors (see below), whose sum is σ = 79760595376. Its totient is φ = 77414695380.

The previous prime is 78587645371. The next prime is 78587645393. The reversal of 78587645377 is 77354678587.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-78587645377 is a prime.

It is a super-2 number, since 2×78587645377² (a number of 23 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (67), and also a Moran number because the ratio is a prime number: 1172949931 = 78587645377 / (7 + 8 + 5 + 8 + 7 + 6 + 4 + 5 + 3 + 7 + 7).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78587645371) 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, 586474899 + ... + 586475032.

It is an arithmetic number, because the mean of its divisors is an integer number (19940148844).

Almost surely, 2^78587645377 is an apocalyptic number.

It is an amenable number.

78587645377 is a deficient number, since it is larger than the sum of its proper divisors (1172949999).

78587645377 is a wasteful number, since it uses less digits than its factorization.

78587645377 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1172949998.

The product of its digits is 276595200, while the sum is 67.

The spelling of 78587645377 in words is "seventy-eight billion, five hundred eighty-seven million, six hundred forty-five thousand, three hundred seventy-seven".