78218821308355 has 16 divisors (see below), whose sum is σ = 115523182240704. Its totient is φ = 49509935245440.

The previous prime is 78218821308293. The next prime is 78218821308361. The reversal of 78218821308355 is 55380312881287.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-78218821308355 is a prime.

It is a super-2 number, since 2×78218821308355² (a number of 29 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 78218821308293 and 78218821308302.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 85954748236 + ... + 85954749145.

It is an arithmetic number, because the mean of its divisors is an integer number (7220198890044).

Almost surely, 2^{78218821308355} is an apocalyptic number.

78218821308355 is a deficient number, since it is larger than the sum of its proper divisors (37304360932349).

78218821308355 is a wasteful number, since it uses less digits than its factorization.

78218821308355 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 171909497406.

The product of its (nonzero) digits is 25804800, while the sum is 61.

The spelling of 78218821308355 in words is "seventy-eight trillion, two hundred eighteen billion, eight hundred twenty-one million, three hundred eight thousand, three hundred fifty-five".