78220618438 has 8 divisors (see below), whose sum is σ = 117403047432. Its totient is φ = 39086269296.

The previous prime is 78220618423. The next prime is 78220618451. The reversal of 78220618438 is 83481602287.

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

It is a super-2 number, since 2×78220618438² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 78220618391 and 78220618400.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12015895 + ... + 12022402.

It is an arithmetic number, because the mean of its divisors is an integer number (14675380929).

Almost surely, 2^78220618438 is an apocalyptic number.

78220618438 is a deficient number, since it is larger than the sum of its proper divisors (39182428994).

78220618438 is a wasteful number, since it uses less digits than its factorization.

78220618438 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24039926.

The product of its (nonzero) digits is 1032192, while the sum is 49.

The spelling of 78220618438 in words is "seventy-eight billion, two hundred twenty million, six hundred eighteen thousand, four hundred thirty-eight".