12491233578 has 12 divisors (see below), whose sum is σ = 27064339458. Its totient is φ = 4163744520.

The previous prime is 12491233577. The next prime is 12491233583. The reversal of 12491233578 is 87533219421.

It is a happy number.

12491233578 is a `hidden beast` number, since 1 + 2 + 49 + 1 + 2 + 33 + 578 = 666.

It can be written as a sum of positive squares in only one way, i.e., 12427121529 + 64112049 = 111477^2 + 8007^2 .

It is not an unprimeable number, because it can be changed into a prime (12491233577) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 346978693 + ... + 346978728.

Almost surely, 2^12491233578 is an apocalyptic number.

12491233578 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

12491233578 is an abundant number, since it is smaller than the sum of its proper divisors (14573105880).

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

12491233578 is a wasteful number, since it uses less digits than its factorization.

12491233578 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 693957429 (or 693957426 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The spelling of 12491233578 in words is "twelve billion, four hundred ninety-one million, two hundred thirty-three thousand, five hundred seventy-eight".