12001211209978 has 32 divisors (see below), whose sum is σ = 19041040327680. Its totient is φ = 5657295150000.

The previous prime is 12001211209943. The next prime is 12001211209987. The reversal of 12001211209978 is 87990211210021.

It is a happy number.

It is a super-2 number, since 2×12001211209978² (a number of 27 digits) contains 22 as substring.

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, 10631743 + ... + 11706253.

It is an arithmetic number, because the mean of its divisors is an integer number (595032510240).

Almost surely, 2^{12001211209978} is an apocalyptic number.

12001211209978 is a deficient number, since it is larger than the sum of its proper divisors (7039829117702).

12001211209978 is a wasteful number, since it uses less digits than its factorization.

12001211209978 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1075954.

The product of its (nonzero) digits is 36288, while the sum is 43.

Adding to 12001211209978 its sum of digits (43), we get a palindrome (12001211210021).

Adding to 12001211209978 its reverse (87990211210021), we get a palindrome (99991422419999).

The spelling of 12001211209978 in words is "twelve trillion, one billion, two hundred eleven million, two hundred nine thousand, nine hundred seventy-eight".