12201778 has 4 divisors (see below), whose sum is σ = 18302670. Its totient is φ = 6100888.

The previous prime is 12201757. The next prime is 12201793. The reversal of 12201778 is 87710221.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 12201049 + 729 = 3493^2 + 27^2 .

It is a super-2 number, since 2×12201778² = 297766772722568, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3050443 + ... + 3050446.

Almost surely, 2^12201778 is an apocalyptic number.

12201778 is a deficient number, since it is larger than the sum of its proper divisors (6100892).

12201778 is an equidigital number, since it uses as much as digits as its factorization.

12201778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6100891.

The product of its (nonzero) digits is 1568, while the sum is 28.

The square root of 12201778 is about 3493.1043500016. The cubic root of 12201778 is about 230.2189345695.

Adding to 12201778 its reverse (87710221), we get a palindrome (99911999).

The spelling of 12201778 in words is "twelve million, two hundred one thousand, seven hundred seventy-eight".