1200120021091 has 4 divisors (see below), whose sum is σ = 1213604515800. Its totient is φ = 1186635526384.

The previous prime is 1200120021049. The next prime is 1200120021109. The reversal of 1200120021091 is 1901200210021.

It is a happy number.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1200120021091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1200120021031) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 6742247221 + ... + 6742247398.

It is an arithmetic number, because the mean of its divisors is an integer number (303401128950).

Almost surely, 2^{1200120021091} is an apocalyptic number.

1200120021091 is a deficient number, since it is larger than the sum of its proper divisors (13484494709).

1200120021091 is an equidigital number, since it uses as much as digits as its factorization.

1200120021091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13484494708.

The product of its (nonzero) digits is 72, while the sum is 19.

The spelling of 1200120021091 in words is "one trillion, two hundred billion, one hundred twenty million, twenty-one thousand, ninety-one".