1200920191021 has 8 divisors (see below), whose sum is σ = 1216062030744. Its totient is φ = 1185842107200.

The previous prime is 1200920190991. The next prime is 1200920191061. The reversal of 1200920191021 is 1201910290021.

It can be written as a sum of positive squares in 4 ways, for example, as 829538424100 + 371381766921 = 910790^2 + 609411^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 1200920191021 - 2⁵ = 1200920190989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1200920191061) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15901066 + ... + 15976411.

It is an arithmetic number, because the mean of its divisors is an integer number (152007753843).

Almost surely, 2^{1200920191021} is an apocalyptic number.

It is an amenable number.

1200920191021 is a deficient number, since it is larger than the sum of its proper divisors (15141839723).

1200920191021 is a wasteful number, since it uses less digits than its factorization.

1200920191021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31877951.

The product of its (nonzero) digits is 648, while the sum is 28.

The spelling of 1200920191021 in words is "one trillion, two hundred billion, nine hundred twenty million, one hundred ninety-one thousand, twenty-one".