1221212001986 has 16 divisors (see below), whose sum is σ = 1928614730400. Its totient is φ = 578353267008.

The previous prime is 1221212001979. The next prime is 1221212001991. The reversal of 1221212001986 is 6891002121221.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3017600 + ... + 3398283.

It is an arithmetic number, because the mean of its divisors is an integer number (120538420650).

Almost surely, 2^{1221212001986} is an apocalyptic number.

1221212001986 is a deficient number, since it is larger than the sum of its proper divisors (707402728414).

1221212001986 is a wasteful number, since it uses less digits than its factorization.

1221212001986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6420913.

The product of its (nonzero) digits is 6912, while the sum is 35.

The spelling of 1221212001986 in words is "one trillion, two hundred twenty-one billion, two hundred twelve million, one thousand, nine hundred eighty-six".