1223523788778 has 24 divisors (see below), whose sum is σ = 2665614449316. Its totient is φ = 405587995200.

The previous prime is 1223523788743. The next prime is 1223523788783. The reversal of 1223523788778 is 8778873253221.

1223523788778 is a `hidden beast` number, since 1 + 2 + 23 + 523 + 7 + 8 + 87 + 7 + 8 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 814439466369 + 409084322409 = 902463^2 + 639597^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 187768963 + ... + 187775478.

Almost surely, 2^{1223523788778} is an apocalyptic number.

1223523788778 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1223523788778 is an abundant number, since it is smaller than the sum of its proper divisors (1442090660538).

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

1223523788778 is a wasteful number, since it uses less digits than its factorization.

1223523788778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 375544630 (or 375544627 counting only the distinct ones).

The product of its digits is 63221760, while the sum is 63.

The spelling of 1223523788778 in words is "one trillion, two hundred twenty-three billion, five hundred twenty-three million, seven hundred eighty-eight thousand, seven hundred seventy-eight".