1221201986 has 8 divisors (see below), whose sum is σ = 1832939280. Its totient is φ = 610222228.

The previous prime is 1221201979. The next prime is 1221202007. The reversal of 1221201986 is 6891021221.

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

It is a super-2 number, since 2×1221201986² = 2982668581220688392, which contains 22 as substring.

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, 185336 + ... + 191811.

It is an arithmetic number, because the mean of its divisors is an integer number (229117410).

Almost surely, 2^1221201986 is an apocalyptic number.

1221201986 is a deficient number, since it is larger than the sum of its proper divisors (611737294).

1221201986 is a wasteful number, since it uses less digits than its factorization.

1221201986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 378768.

The product of its (nonzero) digits is 3456, while the sum is 32.

The square root of 1221201986 is about 34945.7005366898. The cubic root of 1221201986 is about 1068.8805323918.

The spelling of 1221201986 in words is "one billion, two hundred twenty-one million, two hundred one thousand, nine hundred eighty-six".